Fluorine-substituted benzene derivative, liquid-crystal composition, and liquid-crystal display element

ABSTRACT

Liquid crystalline compounds are provided which have an extremely high voltage holding ratio, altered only slightly by change of temperature, and which have a low threshold voltage and a high Δn. Also provided are liquid crystal compositions containing the liquid crystalline compound; and liquid crystal display devices containing the liquid crystal composition. The liquid crystalline compound is expressed by the general formula (1)                    
     wherein R, Y 1  to Y 16 , X and Z 1  to Z 3  are defined in claim  1.

This application is a 371 application of International Application No.PCT/JP97/04331 filed Nov. 27, 1997.

TECHNICAL FIELD

The present invention relates to novel liquid crystalline compounds,liquid crystal compositions, and liquid crystal display devicesfabricated by using the liquid crystal composition. More specifically,the invention relates to liquid crystalline compounds having fluorinesubstituted 1,4-phenylene group, liquid crystal composition comprisingthe liquid crystalline compound, and liquid crystal display devicesfabricated by using the liquid crystal composition.

BACKGROUND ART

Display devices produced by using liquid crystalline compounds (the term“liquid crystalline compound(s)” is used in this specification as ageneral term for the compounds which exhibit a liquid crystal phase andfor the compounds which do not exhibit a liquid crystal phase but areuseful as component of liquid crystal compositions) have widely beenutilized for the display of watches, tabletop calculators, wordprocessors, or the likes. In recent years, researches on TFT typedisplays having characteristics such as a high contrast and wide visualangle are extensively conducted.

For liquid crystal compositions used for TFT, physical properties suchas voltage holding ratio is high, threshold voltage (Vth) is low, theiralteration caused by the change of temperature is small, temperaturerange of liquid crystal phase is wide, miscibility with other liquidcrystal materials is excellent, and viscosity is low have been sought.Further, liquid crystal compositions having a high optical anisotropy(Δn) are useful for increasing response speed.

For these purposes, fluorine containing compounds are suitable. Manyresearches have been conducted up to now and for example, (1) JapanesePatent Publication No. Sho 63-13411, (2) Japanese Patent Publication No.Sho 63-44132, (3) Laid-open Japanese Patent Publication No. Hei2-233626, (4) Laid-open PCT Japanese Publication (Tokuhyo) No. Hei2-501311, (5) Laid-open PCT Japanese Publication No. Hei 3-500413, (6)Laid-open PCT Japanese Publication No. Hei 2-501071, (7) Laid-open PCTJapanese Publication No. Hei 3-503711, (8) Laid-open Japanese PatentPublication No. Hei 4-217930, (9) Laid-open PCT Japanese Publication No.Hei 4-501575, (10) Laid-open PCT Japanese Publication No. Hei 6-504032,and (11) EP-439089 are published.

A part of the compounds of the present invention are formally includedin the general formula disclosed in the publications (6) to (11)mentioned above. However, data such as physical property values of thecompounds which correspond to the ones of the present invention are notdisclosed at all and their specific characteristics are not specificallydescribed in any one of the publications mentioned above. Accordingly,those publications have not suggested the present invention.

DISCLOSURE OF THE INVENTION

In view of the required characteristics described above in relation toliquid crystal compositions for TFT, an object of the present inventionis to provide (a) liquid crystalline compounds which have an extremelyhigh voltage holding ratio, are small in its alteration caused by thechange of temperature, have a low threshold voltage and high Δn; (b)liquid crystal compositions comprising the compound; and (c) liquidcrystal display devices fabricated by using the liquid crystalcomposition.

As a result of a diligent investigation by the present inventors, it hasbeen found out that the liquid crystalline compounds expressed by thefollowing general formula (1) have intended properties, leading to theaccomplishment of the present invention:

wherein R represents an alkyl group having 1 to 20 carbon atoms in whichalkyl group any not-adjacent methylene group (—CH₂—) may be replaced byoxygen (—O—) atom; Y₁ to Y₁₆ independently represent hydrogen atom orfluorine atom, but at least three of them are fluorine atoms, providedthat in no case three or more hydrogen atoms of one 1,4-phenylene groupare replaced by fluorine atom; X represents a halogen atom or an alkylgroup having 1 to 20 carbon atoms in which alkyl group any not-adjacentmethylene group may be replaced by oxygen atom, and any hydrogen atom inthe alkyl group may be replaced by fluorine atom; Z₁, Z₂, and Z₃independently represent —(CH₂)₂—, —(CH₂)₄—, —CH₂O—, —OCH₂—, —(CH₂)₃O—,—O(CH₂)₃—, or single bond; and any atom which constitutes this compoundmay be replaced by its isotope; provided that

when X=—OCF₂CF₂H, Z₁=Z₃=single bond, and Z₂=—(CH₂)₂—, in no case

Y₆=Y₁₀=Y₁₂F, and Y₁ to Y₅=Y₇ to Y₉=Y₁₁=Y₁₃ to Y₁₆=H,

Y₂=Y₁₀=Y₁₂=F, and Y₁=Y₃ to Y₉=Y₁₁=Y₁₃ to Y₁₆=H, or

Y₂=Y₄=Y₁₀=Y₁₂=F, and Y₁=Y₃=Y₅ to Y₉=Y₁₁=Y₁₃ to Y₁₆=H.

Compounds expressed by the general formula (1) are classified asfollows:

In the following formulas (1a) to (1h), R and X have the same meaning asdescribed above, Za to Zc independently represent —(CH₂)₂—, —(CH₂)₄—,—CH₂O—, —OCH₂—, —(CH₂)₃O—, or —O(CH₂)₃—, and P represents 1,4-phenylenegroup in which any one or two hydrogen atoms may be replaced by fluorineatom.

R—P—P—P—P—X  (1a)

R—P—Za—P—P—P—X  (1b)

R—P—P—Zb—P—P—X  (1c)

R—P—P—P—Zc—P—X  (1d)

R—P—Za—P—Zb—P—P—X  (1e)

R—P—Za—P—P—Zc—P—X  (1f)

R—P—P—Zb—P—Zc—P—X  (1g)

R—P—Za—P—Zb—P—Zc—P—X  (1h)

Among these compounds, compounds expressed by one of the formulas (1a)to (1d) are especially preferable for achieving the purpose of thepresent invention.

Among these formulas, R is a straight chain or branched alkyl grouphaving 1 to 20 carbon atoms. As the straight chain alkyl group, methyl,ethyl, propyl, butyl, pentyl, hexyl, heptyl, decyl, pentadecyl, andicosyl; and as branched alkyl group, isopropyl, sec-butyl, tert-butyl,2-methyl-butyl, isopentyl, isohexyl, 3-ethyloctyl, and3,8-dimethyltetradecyl can specifically be mentioned.

In these alkyl groups, any methylene group (—CH₂—) may be replaced byoxygen (—O—) unless oxygen atom continues. As examples of alkyl groupsin which methylene group is replaced by oxygen, alkoxy groups andalkoxyalkyl groups can be mentioned.

As more specific examples of these groups, alkoxy groups such asmethoxy, ethoxy, propoxy, butoxy, pentyloxy, and nonyloxy; alkoxyalkylgroups such as methoxymethyl, methoxyethyl, methoxypropyl, methoxybutyl,methoxypentyl, methoxyoctyl, ethoxymethyl, ethoxyethyl, ethoxypropyl,ethoxyhexyl, propoxymethyl, propoxyethyl, propoxypropyl, propoxypentyl,butoxymethyl, butoxyethyl, butoxybutyl, pentyloxymethyl, pentyloxybutyl,hexyloxymethyl, hexyloxyethyl, hexyloxypropyl, heptyloxymethyl, andoctyloxymethyl can be mentioned.

X represents a halogen atom or an alkyl group having 1 to 20 carbonatoms. In this alkyl group, any methylene group (—CH₂—) may be replacedby oxygen (—O—) unless oxygen atom continues, and hydrogen atom in thegroup may be replaced by fluorine atom. Specifically, the alkyl groups,alkoxy groups, and alkoxyalkyl groups described above can be mentionedas examples.

Further, as fluoroalkyl group, fluoromethyl, difluoromethyl,trifluoromethyl, 1,1,2,2-tetrafluoroethyl, perfluoroethyl,1,1,2,2-tetrafluoropropyl, 1,1,3,3-tetrafluoropropyl,2,2,3,3-tetrafluoropropyl, 1,1,2,3-tetrafluoropropyl,1,2,2,3-tetrafluoropropyl, 1,2,3,3-tetrafluropropyl,1,1,3,3,3-pentafluoropropyl, 1,1,2,3,3,3-hexafluoropropyl,1,1,4,4,4-pentafluoro-butyl, 1,2,5,5-tetrafluoropentyl, andperfluoroicosyl;

as fluoroalkoxy group, difluoromethoxy, trifluoromethoxy,1,1,2,2-tetrafluoroethoxy, perfluoroethoxy, 1,1,2,2-tetrafluoropropoxy,1,1,3,3-tetrafluoropropoxy, 1,1,3,3,3-pentafluoropropoxy,1,1,2,3,3,3-hexafluoropropoxy, 1,1,4,4,4-pentafluorobutoxy, and1,1,2,3,5,5,5-heptafluoropentyloxy; and

as alkoxyalkyl group replaced by fluorine,(trifluoromethoxy)fluoromethyl, (1,1,2,2-tetrafluoroethoxy)methyl,1,2,2,2-tetrafluroethoxy)methyl, (perfluoroethoxy)methyl,(1,1,3,3-tetrafluoropropoxy)methyl,(1,1,3,3,3-pentafluoropropoxy)methyl,(1,1,2,3,3,3-hexafluropropoxy)methyl,(1,1,4,4,4-pentafluorobutoxy)methyl, 2-(1,1,2,2-tetrafluoroethoxy)ethyl,2-(perfluoroethoxy)ethyl, 2-(1,1,3,3,3-pentafluoropropoxy)ethyl,2-(1,1,2,3,3,3-hexafluoropropoxy)ethyl,2-(1,1,2,2-tetrafluroethoxy)propyl, 3-(perfluroethoxy)propyl,2-(1,1,3,3,3-pentafluoropropoxy)propyl,2-(1,1,2,3,3,3-hexafluoropropoxy) propyl,4-(1,1,2,2-tetrafluoroethoxy)butyl,4-(1,1,2,3,3,3-hexafluoropropoxy)butyl,5-(1,2,2,2-tetrafluoroethoxy)pentyl, and5-(1,1,3,3,3-pentafluoropropoxy)pentyl can be mentioned as examples.

Compounds in which the R and/or X described above is an optically activegroup are particularly useful as chiral dopant.

In the general formula (1), while Z₁, Z₂₁ and Z₃ independently represent—(CH₂)₂—, —(CH₂ )₄—, —CH₂O—, —OCH₂—, —(CH₂)₃O—, —O(CH₂)₃—, or singlebond, they are preferably —(CH₂)₂—, —(CH₂)₄—, —CH₂O—, —OCH₂—, or singlebond, and more desirably —(CH₂)₂— or single bond.

Compounds of the present invention exhibit a comparatively high phasetransition temperature to an isotropic phase.

Compounds of the present invention have a positive and extremely highΔε, and a low threshold voltage when X is a strong polar group such as ahalogen atom or CF₃, and the compounds exhibit a comparatively lowviscosity when the X is a weak polar group such as an alkyl group andalkoxy group.

Whereas some of the compounds of the present invention exhibit anegative Δε value, these compounds are suitable as component of liquidcrystal compositions for in-plane switching (IPS) mode and verticalalignment (VA) mode.

Further, an atom which constitutes the compounds expressed by thegeneral formula (1) may be replaced by its isotope. Even in such case,the compounds exhibit characteristics equal to those of the compounds inwhich any atom is not replaced by the isotope.

By properly selecting these substituents and bonding groups, compoundshaving desired physical properties can be obtained.

Liquid crystalline compounds of the present invention expressed by thegeneral formula (1) can be manufactured by ordinary methods of organicsynthesis, and can conveniently be produced, for example, by thefollowing methods:

wherein R, X, Y₁ to Y₁₆, Z₁, Z₃, and m have the same meaning asdescribed above, Xa and Xb represent a halogen atom, n is 1 or 2, and pis 1 or 3.

That is, as shown in scheme 1, Compound (1) of the present invention canbe produced by reacting Compound (4) with Compound (5) in a mixedsolvent of toluene, xylene, or the like, an alcohol such as ethanol, andwater in the presence of a base such as K₂CO₃ or Na₂CO₃, and a catalystsuch as palladium carried on carbon (Pd—C), Pd(PPh₃)₄, and PdCl₂(PPh₃)₂.

Alternatively, as shown in scheme 2, Compound (1) can be produced evenby reacting Compound (4) with a lithium compound such as n-BuLi andsec-BuLi, and a zinc compound such as ZnCl₂ and ZnBr₂, and then reactingwith Compound (6).

As shown in scheme 3, Compound (2) of the present invention can beproduced by lithiating Compound (7) and then reacting with a zinccompound and Compound (6).

Also, as shown in scheme 4, Compound (3) of the present invention can beproduced by reacting Compound (8) with Compound (9) in a solvent such asdimethyl sulfoxide, dimethyl formamide, 1,2-dimethoxyethane,tetrahydrofuran, hexamethylphosphoric triamide, and toluene in thepresence of a base such as sodium amide (J. B. Wright et al., Journal ofthe American Chemical society, 70, 3098 (1948)), potassium carbonate (W.T. Olson et al., Journal of the American Chemical Society, 69, 2451(1947)), triethyl amine (R. L. Merker et al., The Journal of OrganicChemistry, 26, 5180 (1961)), sodium hydroxide (C. Wilkins, Synthesis,156 (1973)), potassium hydroxide (J. Rebek et al., The Journal ofOrganic Chemistry, 44, 1485 (1979)), barium hydroxide (Kawabe et al.,The Journal of Organic Chemistry, 37, 4210 (1972)), or sodium hydride(C. J. Stark, Tetrahedron Letters, 22, 2089 (1981), and K. Takai et al.,Tetrahedron Letters, 21, 1657 (1980)).

Substituent X can readily be introduced into benzene ring at any stageby using a starting material in which the substituent is introduced inadvance, or by using a known method. Some of their specific examples areshown below.

wherein R have the same meaning as described above and Al represents thefollowing group:

wherein Y₁ to Y₁₆ and Z₁ to Z₃ have the same meaning as described above.

That is, as shown in scheme 5, Compound (10) is reacted with a lithiumcompound such as n-butyl lithium and iodine to convert it into Compound(11). Subsequently, the Compound (11) can be reacted with sodiumtrifluoroacetate/copper iodide (I) (G. E. Carr et al., Journal of theChemical Society Perkin Transactions I, 921 (1988)) or methylfluorosulfonyldifluoroacetate/copper iodide (I) (Q. Y. Chen et al.,Journal of the Chemical Society Chemical Communications, 705 (1989)) toproduce trifluoromethyl compound (12).

As shown in scheme 6, Compound (10) can be reacted with a lithiumcompound such as n-butyl lithium, and a formylating agent such asN-formylpiperidine (G. A. Olah et al., Angewandte Chemie InternationalEdition in English, 20, 878 (1981)), N-formylmorpholine (G. A. Olah etal., The Journal of Organic Chemistry, 49, 385 (1984)), and DMF (G. Bosset al., Chemische Berichte, 1199 (1989)) to convert it into Compound(13), and then reacting the compound with a fluorinating agent such asdiethylaminosulfur trifluoride (DAST) (W. J. Middleton et al., TheJournal of Organic Chemistry, 40, 574 (1975), S. Rozen et al.,Tetrahedron Letters, 41, 111 (1985), M. Hudlicky, Organic Reactions, 35,513 (1988), and P. A. Messina et al., Journal of Fluorine Chemistry, 42,137 (1989)), and morpholinosulfur trifluoride (K. C, Mange et al., TheJournal of Fluorine Chemistry, 43, 405 (1989)) to produce difluoromethylcompound (14).

As shown in scheme 7, Compound (13) can be reduced with a reducing agentsuch as sodium borohydride (SBH), lithium aluminum hydride, diisobutylaluminum hydride, and sodium bis(2-methoxyethoxy)aluminum hydride toform Compound (15) and then reacted with a fluorinating agent such asDAST to produce monofluoromethyl compound (16).

As shown in scheme 8, Compound (17) is converted into Compound (18) bythe method of Albert et al. (Synthetic Communications, 19, 547 (1989).This compound can be fluorinated by the method of Kurohoshi et al.(Tetrahedron Letters, 33, 29, 4173 (1992) to produce trifluoromethoxycompound (19).

Further, as shown in scheme 9, Compound (17) can be fluorinated in asystem of chlorodif luoromethane/sodium hydroxide (Laid-open PCTJapanese Publication No. Hei 3-500413) to produce difluoromethoxycompound (20). Alternatively, it can be produced even by the method ofChen et al. (The Journal of Fluorine Chemistry, 44, 433 (1989).

While halogen compounds and dihydroxyborane derivatives which arestaring materials can also be produced by general methods of organicsynthesis, they can conveniently be produced, for example, by thefollowing method:

wherein R, Y₁ to Y₄, and Xa have the same meaning as described above.

That is, as shown in scheme 10, halogen compound (22) can be produced byreacting Compound (21) with a lithium compound such as n-BuLi, andiodine, bromine, or the like.

Further, as shown in scheme 11, dihydroxyborane derivative (23) can beproduced by reacting a Grignard reagent prepared from compound (22) andmagnesium, with a borane derivative such as trimethoxyborane andtriisopropyloxyborane, and then hydrolyzing with hydrochloric acid orthe like.

Intended compounds of the present invention can be produced by using thereactions described above in combination depending on the properties ofthe compounds to be produced. Reactions described above are all known inpublic, and it is needless to say that other known reactions can be usedwhen necessary.

Liquid crystalline compounds of the present invention obtained by suchmethods have an extremely high voltage holding ratio, are considerablysmall in its alteration by the change of temperature, and have a lowthreshold voltage and a high Δn.

Further, these liquid crystalline compounds of the present invention aresufficiently stable chemically and physically under conditions whereinliquid crystal display devices are ordinarily used, and are remarkablyexcellent as component of nematic liquid crystal compositions.

The compounds of the present invention can suitably used as componenteven in liquid crystal compositions for TN, STN, TFT, or other displaymodes.

Liquid crystal compositions of the present invention will be describedbelow.

Liquid crystal compositions of the present invention preferably compriseat least one compound expressed by the general formula (1) in a ratio of0.1 to 99.9% by weight to develop excellent characteristics, and theratio is more preferably 1 to 60% by weight.

In more detail, the liquid crystal compositions of the present inventionare completed by mixing a compound selected from the group consisting ofthe compounds expressed by one of the general formulas (2) to (12)depending on the purposes of the liquid crystal compositions to beproduced, in addition to a first component comprising at least onecompound of the general formula (1).

wherein R₁ represents an alkyl group having 1 to 10 carbon atoms inwhich alkyl group any not-adjacent methylene group may be replaced byoxygen atom or —CH═CH—, and any hydrogen atom in the alkyl group may bereplaced by fluorine atom; X₁ represents fluorine atom, chlorine atom,—OCF₃, —OCF₂H, —CF₃, —CF₂H, —CFH₂, —OCF₂CF₂H, or —OCF₂CFHCF₃; L₁ and L₂independently represent hydrogen atom or fluorine atom; Z₄ and Z₅independently represent 1,2-ethylene group, 1,4-butylene group, —COO—,—CF₂O—, —OCF₂—, —CH═CH—, or single bond; ring B representstrans-1,4-cyclohexylene or 1,3-dioxane-2,5-diyl, or 1,4-phenylene inwhich hydrogen atom may be replaced by fluorine atom; ring C representstrans-1,4-cyclohexylene, or 1,4-phenylene in which hydrogen atom may bereplaced by fluorine atom; and any atom which constitutes thesecompounds may be replaced by its isotope,

wherein R₂ and R₃ independently represent an alkyl group having 1 to 10carbon atoms in which alkyl group any not-adjacent methylene group maybe replaced by oxygen atom or —CH═CH—, and any hydrogen atom in thealkyl group may be replaced by fluorine atom; X₂ represents —CN or—C≡C—CN; ring D represents trans-1,4-cyclohexylene, 1,4-phenylene,1,3-dioxane-2,5-diyl, or pyrimidine-2,5-diyl; ring E representstrans-1,4-cyclohexylene or pyrimidine-2,5-diyl, or 1,4-phenylene inwhich hydrogen atom may be replaced by fluorine atom; ring F representstrans-1,4-cyclohexylene or 1,4-phenylene; Z₆ represents 1,2-ethylenegroup, —COO—, or single bond; L₃, L₄, and L₅ independently representhydrogen atom or fluorine atom; b, c, and d are independently 0 or 1;and any atom which constitutes these compounds may be replaced by itsisotope,

wherein R₄ and R₅ independently represent an alkyl group having 1 to 10carbon atoms in which alkyl group any not-adjacent methylene group maybe replaced by oxygen atom or —CH═CH—, and any hydrogen atom in thealkyl group may be replaced by fluorine atom; ring G, ring 1, and ring Jindependently represent trans-1,4-cyclohexylene or pyrimidine-2,5-diyl,or 1,4-phenylene in which hydrogen atom may be replaced by fluorineatom; Z₇ and Z₈ independently represent —C≡C—, —COO—, —CH₂CH₂—, —CH═CH—,or single bond; and any atom which constitutes these compounds may bereplaced by its isotope,

wherein R₆ and R₇ independently represent an alkyl group having 1 to 10carbon atoms in which alkyl group any not-adjacent methylene group maybe replaced by oxygen atom or —CH═CH—, and any hydrogen atom in thealkyl group may be replaced by fluorine atom; ring K and ring Mindependently represent trans-1,4-cyclohexylene or 1,4-phenylene; L₆ andL₇ independently represent hydrogen atom or fluorine atom, but in nocase L₆ and L₇ simultaneously represent hydrogen atom; Z₉ and Z₁₀independently represent —CH₂CH₂—, —COO—, or single bond; and any atomwhich constitutes these compounds may be replaced by its isotopes.

As the compounds used in the liquid crystal compositions of the presentinvention and expressed by one of the general formulas (2) to (4), thefollowing compounds can preferably be mentioned:

wherein R₁ and X₁ have the same meaning as described above.

Compounds expressed by one of the general formulas (2) to (4) have apositive dielectric anisotropy value, are remarkably excellent inthermal stability and chemical stability, and are indispensable whenliquid crystal compositions for TFT are produced of which a highreliability such as a particularly high voltage holding ratio or largespecific resistivity is required.

While the compound expressed by one of the general formulas (2) to (4)can be used in the range of 0.1 to 99.9% by weight based on the totalamount of liquid crystal composition when liquid crystal compositionsfor TFT are produced, the amount is preferably 10 to 97% by weight andmore desirably 40 to 95% by weight. Further, the compound expressed byone of the general formulas (7) to (9) may further be incorporated forthe purpose of adjusting viscosity of liquid crystal compositions. Also,when liquid crystal compositions for STN display mode or TN display modeare produced, the compound expressed by one of the general formulas (2)to (4) can be used. In this case, the amount of the compound to be usedis preferably less than 50% by weight.

As the compounds used in the liquid crystal compositions of the presentinvention and expressed by the general formula (5) or (6), the followingcompounds can preferably be mentioned:

wherein R₂, R₃, and X₂ have the same meaning as described above.

Compounds expressed by the general formula (5) or (6) have a positiveand high dielectric anisotropy value, and are used particularly for thepurpose of lowering threshold voltage of liquid crystal compositions.They are also used for the purpose of adjusting optical anisotropyvalue, and widening nematic range such as raising clearing point.Further, they are used for the purpose of improving the steepness of V-Tcurve of liquid crystal compositions for STN or TN.

Compounds expressed by the general formula (5) or (6) are usefulparticularly when liquid crystal compositions for STN or TN areproduced.

When the amount of the compound expressed by the general formula (5) or(6) to be used is increased, threshold voltage of liquid crystalcompositions lowers and viscosity rises. Accordingly, it is advantageousto use the compound in a large amount so far as the viscosity of liquidcrystal compositions satisfies required characteristics since thecompositions become possible to be driven at a low voltage. While thecompound expressed by the general formula (5) or (6) can be used in anyamount in the range of 0.1 to 99.9% by weight when liquid crystalcompositions for STN or TN are produced, and the range is preferably 10to 97% by weight and more desirably 40 to 95% by weight.

As the compounds used in the liquid crystal compositions of the presentinvention and expressed by any one of the general formulas (7) to (9),the following compounds can preferably be mentioned:

wherein R₄ and R₅ have the same meaning as described above.

Compounds expressed by one of the general formulas (7) to (9) are smallin its absolute value of dielectric anisotropy and are close to neutral.Compounds expressed by the general formula (7) are used principally forthe purpose of adjusting viscosity or adjusting optical anisotropyvalue. Compounds expressed by the general formula (8) or (9) are usedfor the purpose of widening nematic range such as raising clearingpoint, or for the purpose of adjusting optical anisotropy value.

When the amount of the compound expressed by one of the general formulas(7) to (9) is increased, threshold voltage of liquid crystalcompositions rises and viscosity reduces. Accordingly, it is desirableto use the compound in a large amount so far as liquid crystalcompositions satisfy the required value of threshold voltage. The amountof the compound expressed by one of the general formulas (7) to (9) tobe used is preferably less than 40% by weight when liquid crystalcompositions for TFT are produced and the amount is more desirably lessthan 35% by weight. When liquid crystal compositions for STN or TN areproduced, the amount is preferably less than 70% by weight and moredesirably less than 50% by weight.

As preferable examples of the compounds used in the liquid crystalcompositions of the present invention and expressed by one of thegeneral formulas (10) to (12), the following compounds can be mentioned:

wherein R₆ and R₇ have the same meaning as described above.

Compounds expressed by one of the general formulas (10) to (12) have anegative dielectric anisotropy value. Since the compounds expressed bythe general formula (10) are two rings compounds, they are usedprincipally for the purpose of adjusting threshold voltage, adjustingviscosity, or adjusting optical anisotropy value. Compounds expressed bythe general formula (11) are used for the purpose of widening nematicrange such as raising clearing point, or for the purpose of adjustingoptical anisotropy value. Compounds expressed by the general formula(12) are used for the purpose of lowering threshold voltage and for thepurpose of increasing optical anisotropy value in addition to thepurpose of widening nematic range.

Compounds expressed by one of the general formulas (10) to (12) areprincipally used for liquid crystal compositions having a negativeanisotropy value, and when their amount to be used is increased,threshold voltage of the compositions lowers and viscosity increases.Accordingly, it is desirable to use them in a small amount so far as thecompositions satisfy a required value of threshold voltage. However,since absolute value of dielectric anisotropy of these compounds islower than 5, when the amount becomes less than 40% by weight, theliquid crystal compositions sometimes become impossible to be driven ata low voltage. The amount of the compounds expressed by one of thegeneral formulas (10) to (12) to be used is preferably more than 40% byweight when liquid crystal compositions for TFT having a negativedielectric anisotropy value are produced, and the amount is moredesirably 50 to 90% by weight. Further, the compounds expressed by oneof the general formulas (10) to (12) are sometimes mixed to liquidcrystal compositions having a positive dielectric anisotropy value forthe purpose of controlling the elastic constant and regulating the V-Tcurve of the compositions. In this case, the amount of the compoundsexpressed by one of the general formulas (10) to (12) to be used ispreferably less than 30% by weight.

With the exception of such specific cases as liquid crystal compositionsfor OCB (optically Compensated Birefringence) and the likes, anoptically active compound is usually added to the liquid crystalcompositions of the present invention for the purpose of inducinghelical structure of liquid crystal composition to adjust required twistangle and to prevent reverse twist. As the optically active compound,any known optically active compounds ordinarily used for such purposescan be used, but examples of more preferable optically active compoundscan be mentioned as follows:

Liquid crystal compositions of the present invention are usuallyadjusted in their pitch of twist by adding these optically activecompounds thereto. The twist pitch is preferably adjusted in the rangeof 40 to 200 μm in the case of liquid crystal compositions for TFT orTN, and preferably adjusted in the range of 6 to 20 μm in the case ofliquid crystal compositions for STN. In the case for bistable TN mode,it is preferable to adjust the pitch in the range of 1.5 to 4 μm.Further, two or more kind of optically active compounds may be added forthe purpose of adjusting the dependency of pitch on temperature.

Liquid crystal compositions of the present invention can be produced byconventional methods. Generally, a method in which various componentsare dissolved in one another at a high temperature has been adopted.

Further, the liquid crystal compositions of the present invention can beused as ones for guest-host (GH) mode by adding a dichroic dye such asmerocyanine type, styryl type, azo type, azomethine type, azoxy type,quinophthalone type, anthraquinone type, and tetrazine type thereto.Alternatively, the liquid crystal compositions can be used as NCAP whichis prepared by the microencapsulation of a nematic liquid crystal, or asliquid crystal compositions for polymer dispersed liquid crystal displaydevices (PDLCD) represented by polymer net work liquid crystal displaydevices (PNLCD) prepared by forming a polymer of three-dimensionalreticulated structure in a liquid crystal. Still further, the liquidcrystal compositions of the present invention can be used as ones forelectrically controlled birefringence (ECB) mode or dynamic scattering(DS) mode.

As examples of liquid crystal compositions comprising the compound ofthe present invention, the followings can be mentioned. The compounds inComposition Examples, and Examples described below are designated bysymbolizing them according to the definition shown below, and thecompound No. in Composition Examples is given in the same rule as thatshown in Examples.

Ring structure Symbol Ring structure Symbol

B

B(3,5F)

B(2F)

B(3F, 5Cl)

B(3F)

H

B(3Cl)

Py

B(2,3F)

D(3,5)

B(2,3Cl)

Ch

B(2,5F)

B(3,6F) Right side terminal group Rd Symbol —F —F —Cl —CL —CN —C —CF₃—CF₃ —OCF₃ —OCF3 —OCF₂H —OCF₂H —OCF₂CF₂H —OCF₂CF₂H —OCF₂CFHCF₃—OCF₂CFHCF₃ —C_(w)H_(2w+1) —w —OC₂H_(2w+1) —Ow —C_(w)H_(2w)CH═CH₂ —wV—C_(w)H_(2w)CH═CHC_(x)H_(2x+1) —wVx —COOCH₃ —EMe—C_(w)H_(2w)CH═CHC_(x)H_(2x)F —wVxF —CH═CF₂ —VFF —C_(w)H_(2w)CH═CF₂—wVFF —C≡C—CN —TC

Ring structure Symbol Ring structure Symbol

B

B(3,5F)

B(2F)

B(3F,5Cl)

B(3F)

H

B(3Cl)

Py

B(2,3F)

D(3,5)

B(2,3Cl)

Ch

B(2,5F)

B(3,6F) Right side terminal group Rd Symbol —F —F —Cl —CL —CN —C —CF₃—CF₃ —OCF₃ —OCF3 —OCF₂H —OCF₂H —OCF₂CF₂H —OCF₂CF₂H —OCF₂CFHCF₃—OCF₂CFHCF₃ —C_(w)H_(2w+1) —w —OC_(w)H_(2w+1) —Ow —C_(w)H_(2w)CH═CH₂ —wV—C_(w)H_(2w)CH═CHC_(x)H_(2x+1) —wVx —COOCH₃ —EMe—C_(w)H_(2w)CH═CHC_(x)H_(2x)F —wVxF —CH═CF₂ —VFF —C_(w)H_(2w)CH═CF₂—wVFF —C≡C—CN —TC

When hydrogen atom of trans-1,4-cyclohexylene in the following partialstructure was replaced by deuterium (heavy hydrogen) at positions Q₁,Q₂, and Q₃, it is designated by symbol H[1D 2D, 3D], and when thepositions Q₅, Q₆, and Q₇ were replaced by deuterium, it is designated bysymbol H[5D, 6D, 7D]. In other words, the positions where deuteriumsubstituted are indicated by the numeral in the bracket [ ].

In the Composition Examples and Examples, “%” means % by weight and“part” means the amount (part by weight) of an optically active compoundto be added to 100 parts by weight of a liquid crystal compositionunless otherwise specified. When cis·trans isomers exist in particularcompounds, they are trans form.

COMPOSITION EXAMPLE 1

3-B(3F)B(3,5F)B(3F)B(3F)-CL (Compound No. 49) 1.0% 2-BBB(3,5F)B(3F)-OCF₃(Compound No. 10) 1.0% 1V2-BEB(3,5F)-C 5.0% 3-HB-C 25.0%  1-BTB-3 5.0%2-BTB-1 10.0%  3-HH-4 11.0%  3-HHB-1 9.0% 3-HHB-3 9.0% 3-H2BTB-2 4.0%3-H2BTB-3 4.0% 3-H2BTB-4 4.0% 3-HB(3F)TB-2 6.0% 3-HB(3F)TB-3 6.0% CM33  0.8 part

COMPOSITION EXAMPLE 2

2-BBB(3,5F)B(3F)-OCF₃ (Compound No. 10) 2.0% V2-HB-C 12.0%  1V2-HB-C12.0%  3-HB-C 15.0%  3-H[1D,2D,3D]B-C 9.0% 3-HB(3F)-C 5.0% 2-BTB-1 2.0%3-HH-4 8.0% 3-HH-VFF 6.0% 2-H[1D,2D,3D]HB-C 3.0% 3-HHB-C 6.0%3-HB(3F)TB-2 8.0% 3-H2BTB-2 5.0% 3-H2BTB-3 5.0% 3-H2BTB-4 2.0%

COMPOSITION EXAMPLE 3

3-B2B(3F)B(3,5F)B(3F)-F (Compound No. 1) 4.0% 2O1-BEB(3F)-C 5.0%3O1-BEB(3F)-C 15.0%  4O1-BEB(3F)-C 13.0%  5O1-BEB(3F)-C 13.0% 2-HHB(3F)-C 15.0%  3-HHB(3F)-C 15.0%  3-HB(3F)TB-2 4.0% 3-HB(3F)TB-34.0% 3-HHB-1 8.0% 3-HHB-O1 4.0%

COMPOSITION EXAMPLE 4

3-B(3F)B(3,5F)B(3F)B(3F)-CL (Compound No. 49) 1.0% 2-BBB(3,5F)B(3F)-OCF₃(Compound No. 10) 2.0% 5-PyB-F 4.0% 3-PyB(3F)-F 4.0% 2-BB-C 5.0% 4-BB-C4.0% 5-BB-C 5.0% 2-PyB-2 2.0% 3-PyB-2 2.0% 4-PyB-2 2.0% 6-PyB-O5 3.0%6-PyB-O6 3.0% 6-PyB-O7 3.0% 6-PyB-O8 3.0% 3-PyBB-F 6.0% 4-PyBB-F 6.0%5-PyBB-F 6.0% 3-HHB-1 6.0% 3-HHB-3 5.0% 2-H2BTB-2 4.0% 2-H2BTB-3 4.0%2-H2BTB-4 5.0% 3-H2BTB-2 5.0% 3-H2BTB-3 5.0% 3-H2BTB-4 5.0%

COMPOSITION EXAMPLE 5

2-BBB(3,5F)B(3F)-OCF₃ (Compound No. 10) 2.0% 3-B2B(3F)B(3,5F)B(3F)-F(Compound No. 1) 2.0% 3-D(3,5)B-C 10.0%  4-D(3,5)B-C 10.0%  2-BEB-C12.0%  3-BEB-C 4.0% 3-PyB(3F)-F 6.0% 3-HEB-O4 8.0% 4-HEB-O2 6.0%5-HEB-O1 6.0% 3-HEB-O2 5.0% 5-HEB-O2 4.0% 5-HEB-5 5.0% 4-HEB-5 5.0%1O-BEB-2 4.0% 3-HHB-1 4.0% 3-HHEBB-C 3.0% 3-HBEBB-C 2.0% 5-HBEBB-C 2.0%

COMPOSITION EXAMPLE 6

3-B(3F)B(3,5F)B(3F)B(3F)-CL (Compound No. 49) 1.0%3-B2B(3F)B(3,5F)B(3F)-F (Compound No. 1) 5.0% 3-HB-C 18.0%  7-HB-C 3.0%1O1-HB-C 10.0%  3-HB(3F)-C 10.0%  2-PyB-2 2.0% 3-PyB-2 2.0% 4-PyB-2 2.0%1O1-HH-3 7.0% 2-BTB-O1 7.0% 3-HHB-1 7.0% 3-HHB-F 4.0% 3-HHB-O1 4.0%3-HHB-3 5.0% 3-H2BTB-3 3.0% 2-PyBH-3 4.0% 3-PyBH-3 3.0% 3-PyBB-2 3.0%

COMPOSITION EXAMPLE 7

3-B(3F)B(3,5F)B(3F)B(3F)-CL (Compound No. 49) 1.0% 2-BBB(3,5F)B(3F)-OCF₃(Compound No. 10) 2.0% 3-B2B(3F)B(3,5F)B(3F)-F (Compound No. 1) 3.0%2O1-BEB(3F)-C 5.0% 3O1-BEB(3F)-C 12.0%  5O1-BEB(3F)-C 4.0%1V2-BEB(3,5F)-C 10.0%  3-HH-EMe 10.0%  3-HB-O2 18.0%  7-HEB-F 2.0%3-HHEB-F 2.0% 5-HHEB-F 2.0% 3-HBEB-F 4.0% 2O1-HBEB(3F)-C 2.0%3-HB(3F)EB(3F)-C 2.0% 3-HBEB(3,5F)-C 2.0% 3-HHB-F 4.0% 3-HHB-O1 4.0%3-HHB-3 7.0% 3-HEBEB-F 2.0% 3-HEBEB-1 2.0%

COMPOSITION EXAMPLE 8

4O-B(2,3F)BB(2,3F)2B-3 (Compound No. 147) 3.0% 5-BEB(3F)-C 5.0% V-HB-C11.0%  5-PyB-C 6.0% 4-BB-3 11.0%  3-HH-2V 10.0%  5-HH-V 11.0%  V-HHB-17.0% V2-HHB-1 12.0%  3-HHB-1 9.0% 1V2-HBB-2 10.0%  3-HHEBH-3 5.0%

COMPOSITION EXAMPLE 9

3-BB(3,5F)CH₂OBB(3,5F)-CF₃ (Compound No. 179) 2.0% 2O1-BEB(3F)-C 5.0%3O1-BEB(3F)-C 12.0%  5O1-BEB(3F)-C 4.0% 1V2-BEB(3,5F)-C 16.0%  3-HB-O210.0%  3-HH-4 3.0% 3-HHB-F 3.0% 3-HHB-1 8.0% 3-HHB-O1 4.0% 3-HBEB-F 4.0%3-HHEB-F 7.0% 5-HHEB-F 7.0% 3-H2BTB-2 4.0% 3-H2BTB-3 4.0% 3-H2BTB-4 4.0%3-HB(3F)TB-2 3.0%

COMPOSITION EXAMPLE 10

3-B(3F)B(3,5F)B(3F)B(3F)-CL (Compound No. 49) 1.0% 2-BBB(3,5F)B(3F)-OCF₃(Compound No. 10) 1.0% 3-B2B(3F)B(3,5F)B(3F)-F (Compound No. 1) 2.0%2-BEB-C 12.0%  3-BEB-C 4.0% 4-BEB-C 6.0% 3-HB-C 28.0%  3-HEB-O4 12.0% 4-HEB-O2 8.0% 5-HEB-O1 8.0% 3-HEB-O2 6.0% 5-HEB-O2 5.0% 3-HHB-1 3.0%3-HHB-O1 4.0%

COMPOSITION EXAMPLE 11

3-B2B(3F)B(3,5F)B(3F)-F (Compound No. 1) 5.0% 4O-B(2,3F)BB(2,3F)2B-3(Compound No. 147) 3.0% 3-BB(3,5F)CH₂OBB(3,5F)-CF₃ (Compound No. 179)2.0% 2-BEB-C 10.0%  5-BB-C 12.0%  7-BB-C 7.0% 1-BTB-3 7.0% 2-BTB-110.0%  1O-BEB-2 10.0%  1O-BEB-5 12.0%  2-HHB-1 4.0% 3-HHB-F 4.0% 3-HHB-17.0% 3-HHB-O1 4.0% 3-HHB-3 3.0%

COMPOSITION EXAMPLE 12

4O-B(2,3F)BB(2,3F)2B-3 (Compound No. 147) 3.0%3-BB(3,5F)CH₂OBB(3,5F)-CF₃ (Compound No. 179) 2.0% 1V2-BEB(3,5F)-C 8.0%3-HB-C 10.0%  V2V-HB-C 14.0%  V2V-HH-3 19.0%  3-HB-O2 4.0% 3-HHB-110.0%  3-HHB-3 10.0%  3-HB(3F)TB-2 4.0% 3-HB(3F)TB-3 4.0% 3-H2BTB-2 4.0%3-H2BTB-3 4.0% 3-H2BTB-4 4.0%

COMPOSITION EXAMPLE 13

2-BBB(3,5F)B(3F)-OCF₃ (Compound No. 10) 2.0% 3-B2B(3F)B(3,5F)B(3F)-F(Compound No. 1) 2.0% 5-BTB(3F)TB-3 10.0%  V2-HB-TC 10.0%  3-HB-TC10.0%  3-HB-C 10.0%  5-HB-C 7.0% 5-BB-C 3.0% 2-BTB-1 10.0%  2-BTB-O15.0% 3-HH-4 5.0% 3-HHB-1 6.0% 3-HHB-3 11.0%  3-H2BTB-2 3.0% 3-H2BTB-33.0% 3-HB(3F)TB-2 3.0%

COMPOSITION EXAMPLE 14

3-B(3F)B(3,5F)B(3F)B(3F)-CL (Compound No. 49) 1.0%3-B2B(3F)B(3,5F)B(3F)-F (Compound No. 1) 2.0% 1V2-BEB(3,5F)-C 6.0%3-HB-C 18.0%  2-BTB-1 10.0%  5-HH-VFF 30.0%  1-BHH-VFF 8.0% 1-BHH-2VFF11.0%  3-H2BTB-2 2.0% 3-H2BTB-3 4.0% 3-H2BTB-4 4.0% 3-HHB-1 4.0%

COMPOSITION EXAMPLE 15

3-B(3F)B(3,5F)B(3F)B(3F)-CL (Compound No. 49) 1.0% 2-BBB(3,5F)B(3F)-OCF₃(Compound No. 10) 2.0% 3-B2B(3F)B(3,5F)B(3F)-F (Compound No. 1) 3.0%2-HB-C 5.0% 3-HB-C 12.0%  3-HB-O2 15.0%  2-BTB-1 3.0% 3-HHB-1 8.0%3-HHB-F 4.0% 3-HHB-O1 5.0% 3-HHB-3 8.0% 3-HHEB-F 4.0% 5-HHEB-F 4.0%2-HHB(3F)-F 7.0% 3-HHB(3F)-F 7.0% 5-HHB(3F)-F 7.0% 3-HHB(3,5F)-F 5.0%

COMPOSITION EXAMPLE 16

3-B(3F)B(3,5F)B(3F)B(3F)—CL (Compound No. 49) 1.0% 2-BBB(3,5F)B(3F)—OCF₃(Compound No. 10) 1.0% 3-B2B(3F)B(3,5F)B(3F)—F (Compound No. 1) 10.0%4O—B(2,3F)BB(2,3F)2B-3 (Compound No. 147) 2.0%3-BB(3,5F)CH₂OBB(3,5F)—CF₃ (Compound No. 179) 2.0% V2-HB—C 12.0%1V2-HB—C 12.0% 3-HB—C 24.0% 3-HB(3F)—C 5.0% 2-BTB-1 2.0% 3-HH-4 8.0%3-HH—VFF 6.0% 2-HHB—C 3.0% 3-HHB—C 6.0% 3-HB(3F)TB-2 6.0%

COMPOSITION EXAMPLE 17

3-B(3F)B(3,5F)B(3F)B(3F)—CL (Compound No. 49) 1.0% 2-BBB(3,5F)B(3F)—OCF₃(Compound No. 10) 1.0% 3-B2B(3F)B(3,5F)B(3F)—F (Compound No. 1) 5.0%2-HHB(3F)—F 17.0% 3-HHB(3F)—F 17.0% 5-HHB(3F)—F 16.0% 2-H2HB(3F)—F 10.0%3-H2HB(3F)—F 5.0% 5-H2HB(3F)—F 10.0% 2-HBB(3F)—F 6.0% 3-HBB(3F)—F 6.0%5-HBB(3F)—F 6.0% CN 0.3 part

COMPOSITION EXAMPLE 18

2-BBB(3,5F)B(3F)—OCF₃ (Compound No. 10) 2.0% 3-B2B(3F)B(3,5F)B(3F)—F(Compound No. 1) 2.0% 7-HB(3F)—F 5.0% 5-H2B(3F)—F 5.0% 3-HB—O2 10.0%3-HH-4 2.0% 3-HH[5D,6D,7D]-4 3.0% 2-HHB(3F)—F 10.0% 3-HHB(3F)—F 10.0%5-HH[5D,6D,7D]B(3F)—F 10.0% 3-H2HB(3F)—F 5.0% 2-HBB(3F)—F 3.0%3-HBB(3F)—F 3.0% 5-HBB(3F)—F 6.0% 2-H2BB(3F)—F 5.0% 3-H2BB(3F)—F 6.0%3-HHB-1 8.0% 3-HHB—O1 5.0%

COMPOSITION EXAMPLE 19

4O—B(2,3F)BB(2,3F)2B-3 (Compound No. 147) 3.0% 7-HB(3,5F)—F 3.0% 3-HB—O27.0% 2-HHB(3F)—F 10.0% 3-HHB(3F)—F 10.0% 5-HHB(3F)—F 10.0% 2-HBB(3F)—F9.0% 3-HBB(3F)—F 9.0% 5-HBB(3F)—F 16.0% 2-HBB—F 4.0% 3-HBB—F 4.0%3-HBB(3,5F)—F 5.0% 5-HBB(3,5F)—F 10.0%

COMPOSITION EXAMPLE 20

3-BB(3,5F)CH₂OBB(3,5F)—CF₃ (Compound No. 179) 2.0% 7-HB(3,5F)—F 3.0%3-H2HB(3,5F)—F 12.0% 4-H2HB(3,5F)—F 10.0% 5-H2HB(3,5F)—F 8.0%3-HHB(3,5F)—F 5.0% 4-HHB(3,5F)—F 5.0% 3-HH2B(3,5F)—F 15.0%5-HH2B(3,5F)—F 10.0% 3-HBB(3,5F)—F 12.0% 5-HBB(3,5F)—F 12.0%3-HBCF₂OB(3,5F)—F 6.0%

COMPOSITION EXAMPLE 21

3-B(3F)B(3,5F)B(3F)B(3F)—CL (Compound No. 49) 1.0% 2-BBB(3,5F)B(3F)—OCF₃(Compound No. 10) 2.0% 3-B2B(3F)B(3,5F)B(3F)—F (Compound No. 1) 3.0%7-HB(3,5F)—F 5.0% 3-H2HB(3,5F)—F 12.0% 4-H2HB(3,5F)—F 8.0% 3-HHB(3,5F)—F10.0% 4-HHB(3,5F)—F 5.0% 3-HBB(3,5F)—F 10.0% 3-HHEB(3,5F)—F 10.0%4-HHEB(3,5F)—F 3.0% 5-HHEB(3,5F)—F 3.0% 2-HBEB(3,5F)—F 3.0%3-HBEB(3,5F)—F 5.0% 5-HBEB(3,5F)—F 3.0% 3-HD(3,5)B(3,5F)—F 15.0%3-HHBB(3,5F)—F 2.0%

COMPOSITION EXAMPLE 22

3-B2B(3F)B(3,5F)B(3F)—F (Compound No. 1) 5.0% 4O—B(2,3F)BB(2,3F)2B-3(Compound No. 147) 3.0% 3-BB(3,5F)CH₂OBB(3,5F)—CF₃ (Compound No. 179)2.0% 3-HB—CL 10.0% 5-HB—CL 4.0% 7-HB—CL 4.0% 1O1-HH-5 5.0% 2-HBB(3F)—F8.0% 3-HBB(3F)—F 8.0% 5-HBB(3F)—F 9.0% 4-HHB—CL 8.0% 5-HHB—CL 3.0%3-H2HB(3F)—CL 4.0% 3-HBB(3,5F)—F 10.0% 5-H2BB(3,5F)—F 9.0% 3-HB(3F)VB-24.0% 3-HB(3F)VB-3 4.0%

COMPOSITION EXAMPLE 23

2-BBB(3,5F)B(3F)—OCF₃ (Compound No. 10) 2.0% 3-HHB(3,5F)—F 9.0%3-H2HB(3,5F)—F 8.0% 4-H2HB(3,5F)—F 8.0% 5-H2HB(3,5F)—F 8.0%3-HBB(3,5F)—F 21.0% 5-HBB(3,5F)—F 20.0% 3-H2BB(3,5F)—F 10.0%5-HHBB(3,5F)—F 3.0% 5-HHEBB—F 2.0% 3-HH2BB(3,5F)—F 3.0% 1O1-HBBH-4 4.0%1O1-HBBH-5 2.0%

COMPOSITION EXAMPLE 24

3-B2B(3F)B(3,5F)B(3F)—F (Compound No. 1) 2.0% 5-HB—F 12.0% 6-HB—F 9.0%7-HB—F 7.0% 2-HHB—OCF₃ 7.0% 3-HHB—OCF₃ 7.0% 4-HHB—OCF₃ 7.0% 5-HHB—OCF₃5.0% 3-HH2B—OCF₃ 4.0% 5-HH2B—OCF₃ 4.0% 3-HHB(3,5F)—OCF₃ 5.0% 3-HBB(3F)—F10.0% 5-HBB(3F)—F 10.0% 3-HH2B(3F)—F 3.0% 3-HB(3F)BH-3 2.0% 5-HBBH—32.0% 3-HHB(3,5F)—OCF₂H 4.0%

COMPOSITION EXAMPLE 25

3-B(3F)B(3,5F)B(3F)B(3F)—CL (Compound No. 49) 1.0%3-B2B(3F)B(3,5F)B(3F)—F (Compound No. 1) 3.0% 5-H4HB(3,5F)—F 7.0%5-H4HB—OCF₃ 15.0% 3-H4HB(3,5F)—CF₃ 8.0% 5-H4HB(3,5F)—CF₃ 10.0% 3-HB—CL6.0% 5-HB—CL 4.0% 2-H2BB(3F)—F 5.0% 3-H2BB(3F)—F 10.0% 5-HVHB(3,5F)—F5.0% 3-HHB—OCF₃ 3.0% 3-H2HB—OCF₃ 3.0% V—HHB(3F)—F 5.0% 3-HHB(3F)—F 5.0%5-HHEB—OCF₃ 2.0% 3-HBEB(3,5F)—F 5.0% 5-HH—V2F 3.0%

2-BBB(3,5F)B(3F)—OCF₃ (Compound No. 10) 3.0% 3-B2B(3F)B(3,5F)B(3F)—F(Compound No. 1) 3.0% 2-HHB(3F)—F 2.0% 3-HHB(3F)—F 2.0% 5-HHB(3F)—F 2.0%2-HBB(3F)—F 6.0% 3-HBB(3F)—F 6.0% 5-HBB(3F)—F 10.0% 2-H2BB(3F)—F 9.0%3-H2BB(3F)—F 9.0% 3-HBB(3,5F)—F 25.0% 5-HBB(3,5F)—F 19.0% 1O1-HBBH-42.0% 1O1-HBBH-5 2.0%

COMPOSITION EXAMPLE 27

3-B(3F)B(3,5F)B(3F)B(3F)—CL (Compound No. 49) 1.0% 2-BBB(3,5F)B(3F)—OCF₃(Compound No. 10) 1.0% 3-B2B(3F)B(3,5F)B(3F)—F (Compound No. 1) 3.0%5-HB—CL 12.0% 3-HH-4 7.0% 3-HB—O2 20.0% 3-H2HB(3,5F)—F 8.0%3-HHB(3,5F)—F 8.0% 3-HBB(3,5F)—F 6.0% 2-HHB(3F)—F 5.0% 3-HHB(3F)—F 5.0%2-H2HB(3F)—F 2.0% 3-H2HB(3F)—F 1.0% 5-H2HB(3F)—F 2.0% 3-HHBB(3,5F)—F4.0% 3-HBCF₂OB—OCF3 4.0% 5-HBCF₂OB(3,5F)—CF₃ 4.0% 3-HHB-1 3.0% 3-HHB—O14.0%

COMPOSITION EXAMPLE 28

3-B(3F)B(3,5F)B(3F)B(3F)—CL (Compound No. 49) 1.0% 2-BBB(3,5F)B(3F)—OCF₃(Compound No. 10) 1.0% 3-B2B(3F)B(3,5F)B(3F)—F (Compound No. 1) 20.0%4O—B(2,3F)BB(2,3F)2B-3 (Compound No. 147) 3.0%3-BB(3,5F)CH₂OBB(3,5F)—CF₃ (Compound No. 179) 2.0% 2-HHB(3F)—F 17.0%3-HHB(3F)—F 17.0% 5-HHB(3F)—F 4.0% 2-H2HB(3F)—F 10.0% 3-H2HB(3F)—F 5.0%5-H2HB(3F)—F 5.0% 2-HBB(3F)—F 6.0% 3-HBB(3F)—F 6.0% 5-HBB(3F)—F 3.0%

COMPOSITION EXAMPLE 29

2-BBB(3,5F)B(3F)—OCF₃ (Compound No. 10) 1.0% 3-B2B(3F)B(3,5F)B(3F)—F(Compound No. 1) 5.0% 4O—B(2,3F)BB(2,3F)2B-3 (Compound No. 147) 2.0%3-BB(3,5F)CH₂OBB(3,5F)—CF₃ (Compound No. 179) 2.0% 3-BEB(3F)—C 8.0%3-HB—C 8.0% V—HB—C 8.0% 1V—HB—C 8.0% 3-HB—O2 3.0% 3-HH-2V 14.0% 3-HH-2V17.0% V2-HHB-1 10.0% 3-HHB-1 5.0% 3-HHEB—F 7.0% 3-H2BTB—2 6.0% 3-H2BTB-36.0%

COMPOSITION EXAMPLE 30

3-B(3F)B(3,5F)B(3F)B(3F)—CL (Compound No. 49) 1.0% 2-BBB(3,5F)B(3F)—OCF₃(Compound No. 10) 2.0% 3-B2B(3F)B(3,5F)B(3F)—F (Compound No. 1) 2.0%3-H2HB(3,5F)—F 7.0% 5-H2HB(3,5F)—F 8.0% 3-HHB(3,5F)—F 10.0%4-HHB(3,5F)—F 5.0% 3-HH2B(3,5F)—F 9.0% 5-HH2B(3,5F)—F 4.0% 3-HBB(3,5F)—F15.0% 5-HBB(3,5F)—F 15.0% 3-HBEB(3,5F)—F 2.0% 4-HBEB(3,5F)—F 2.0%5-HBEB(3,5F)—F 2.0% 3-HHEB(3,5F)—F 10.0% 4-HHEB(3,5F)—F 3.0%5-HHEB(3,5F)—F 3.0%

COMPOSITION EXAMPLE 31

4O—B(2,3F)BB(2,3F)2B-3 (Compound No. 147) 3.0% 3-HH-5 5.0% 3-HH-4 5.0%3-HH—O1 6.0% 3-HH—O3 6.0% 3-HB—O1 5.0% 3-HB—O2 5.0% 3-HB(2,3F)—O2 10.0%5-HB(2,3F)—O2 10.0% 3-HHB(2,3F)—O2 12.0% 5-HHB(2,3F)—O2 13.0%3-HHB(2,3F)-2 4.0% 5-HHB(2,3F)-1 4.0% 3-HHEH-3 5.0% 3-HHEH-5 5.0%4-HHEH-3 2.0%

BEST MODE FOR CARRYING OUT THE INVENTION

Now, the present invention will be described in more detail withreference to Examples. In each of the Examples, C indicates crystal, SA:smectic phase A, SB: smectic phase B, SX: smectic phase the structure ofwhich has not yet been defined, N: nematic phase, and Iso: isotropicphase, and the unit of all phase transition temperatures is °C.

EXAMPLE 1

Preparation of2″,2′,6′,3,4-pentafluoro-4″-(2-(4-propylphenyl)ethyl)terphenyl(3-B2B(3F)B(3,5F)B(3F)-F (Compound No. 1))

(First step) Preparation of 3-fluoro-4′-propyldeoxybenzoin

In a mixture of 48.9 g (248.8 imol) of (4-propylphenyl)acetylchloride,2.6 g (7.5 mmol) of tris(2,4-pentanedionata)iron (III), and 200 ml oftoluene was added dropwise a solution of a Grignard reagent preparedfrom 56.6 g (323.5 mmol) of 1-bromo-3-fluorobenzene and 8.2 g (335.9mmol) of Mg in 300 ml of tetrahydrofuran (THF) while maintaining them ata temperature lower than −60° C. After finishing of the dropping, theywere stirred at the same temperature for 3 hours. Subsequently, thereaction mixture was raised up to room temperature, 200 ml of a dilutedhydrochloric acid was added dropwise thereto, and then extracted with150 ml of heptane. The organic layer thus obtained was washed with anaqueous sodium bicarbonate solution thrice and with water thrice, andthen dried over anhydrous magnesium sulfate. After the solvent wasdistilled off under a reduced pressure, the residue was subjected tosilica gel column chromatography (eluent: toluene/heptane=8/2) to obtain43.3 g of a crude 3-fluoro-4′-propyldeoxybenzoin. This product wasrecrystallized from methanol to obtain 28.5 g of the subject compound.(Yield: 44.8%)

(Second step) Preparation of 3-fluoro-(2-(4-propylphenyl)ethyl)benzene

After 28 ml (175.6 mol) of triethylsilane was added dropwise to asolution of 15.0 g (58.5 mmol) of the 3-fluoro-4′-propyldeoxybenzoinobtained in the previous step in 40 ml of trifluoroacetic acid whilebeing cooled with ice, they were stirred at room temperature for 3hours.

The reaction solution was extracted with 150 ml of heptane, and theorganic layer thus obtained was washed with an aqueous sodiumbicarbonate solution thrice and with water thrice, and then dried overanhydrous magnesium sulfate. After the solvent was distilled off under areduced pressure, the residue was subjected to silica gel columnchromatography (eluent: heptane) to obtain 4.8 g of a crude3-fluoro-(2-(4-propylphenyl)ethyl)benzene. This product was used fornext reaction without any further purification. (Yield: 33.9%)

(Third step) Preparation of3-fluoro-4-iodo-(2-(4-propylphenyl)ethyl)benzene

In a solution of 4.8 g (19.7 mmol) of the3-fluoro-(2-(4-propylphenyl)ethyl)benzene obtained in the previous stepin 25 ml of THF was added dropwise 23 ml of sec-BuLi (1.04 M,cyclohexane solution, corresponding to 23.7 mmol) while being maintainedat a temperature lower than −60° C., and they were stirred at the sametemperature for 1 hour. Subsequently, a solution of 7.5 g (29.6 mmol) ofiodine in 20 ml of THF was added dropwise to the reaction mixture whilebeing maintained at a temperature lower than −60° C., and they werestirred at the same temperature for 1 hour. The reaction solution waspoured into 50 ml of a diluted aqueous sodium thiosulfate solution, andextracted with 50 ml of heptane. The organic layer thus obtained waswashed with water thrice and then dried over anhydrous magnesiumsulfate. After the solvent was distilled off under a reduced pressure,the residue was subjected to silica gel column chromatography (eluent:heptane) to obtain 6.5 g of a crude3-fluoro-4-iodo-(2-(4-propylphenyl)ethyl)benzene. This product was usedfor next reaction without any further purification. (Yield: 90.2%)

(Fourth step) Preparation of4′-(2-(4-propylphenyl)ethyl)-2′,3,5-trifluorobiphenyl

A mixture of 6.5 g (17.7 mmol) of the3-fluoro-4-iodo(2-(4-propylphenyl)ethyl)benzene obtained in the previousstep, 3.8 g (26.5 mmol) of dihydroxy(3,5-difluorophenyl)borane, 4.9 g(35.3 mmol) of potassium carbonate, 0.5 g of palladium carried on carbon(5%), and 50 ml of toluene/ethanol/water (1/1/1) was heated to refluxfor 15 hours. The catalyst was removed by filtration, the mixture wassubjected to extraction with 250 ml of toluene, the organic layer thusobtained was washed with water thrice, and then dried over anhydrousmagnesium sulfate. The solvent was distilled off under a reducedpressure and the residue thus obtained was subjected to silica gelcolumn chromatography (eluent: heptane/toluene=9/1) to obtain 5.2 g of acrude 4′-(2-(4-propylphenyl)ethyl)-2′,3,5-trifluorobiphenyl. Thisproduct was used for next reaction without any further purification.(Yield: 87.8%)

(Fifth step) Preparation of4′-(2-(4-propylpheny)ethyl)-2′,3,5-trifluoro-4-iodobiphenyl

The same procedures as in the third step were repeated with theexception that 5.2 g (15.5 mmol) of the4′-(2-(4-propylphenyl)ethyl)-2′,3,5-trifluorobiphenyl obtained in thefourth step was used in place of the3-fluoro-(2-(4-propylphenyl)ethyl)benzene used in the third step, andthat 14 ml of n-BuLi (1.66M, THF solution, corresponding to 23.3 mmol)was used in place of sec-BuLi, to obtain 4.3 g of4′-(2-(4-propylphenyl)ethyl)-2′,3,5-trifluoro-4-iodobiphenyl. (Yield:57.4%)

(Sixth step) Preparation of2″,2′,5′,3,4-pentafluoro-4″-(2-(4-propylphenyl)ethyl)terphenyl

The same procedures as in the fourth step were repeated with theexception that 4.3 g (8.9 mmol) of the4′-(2-(4-propylphenyl)ethyl)-2′,3,5-trifluoro-4-iodobiphenyl obtained inthe fifth step was used in place of the3-fluoro-4-iodo-(2-(4-propylphenyl)ethyl)benzene used in the fourthstep, and that 2.1 g (13.3 mmol) of dihydroxy(3,4-difluorophenyl)boranewas used in place of dihydroxy(3,5-difluorophenyl)borane, to obtain 3.4g of a crude2″,2′,6′,3,4-pentafluoro-4″-(2-(4-propylphenyl)ethyl)terphenyl. Thisproduct was recrystallized from mixed solvent of ethanol/ethyl acetate(8/2) to obtain 2.6 g of the subject compound. (Yield: 62.3%) Phasetransition temperatures of this product were as follows:

C 112.5˜113.9 N 118.3˜118.5 Iso

Further, the data of each of the spectrums well supported its structure.

Mass analysis: 466 (M+)

₁H-NMR (CDCl₃, TMS internal standard)

δ (ppm)

0.94 (t, 3H)

1.67 (tq, 2H)

2.57 (t, 2H)

2.94 (s, 4H)

6.94-7.44 (m, 12H)

Examples in which the compounds of the present invention were used ascomponent of liquid crystal compositions are shown below. In each of theUse Examples, NI means phase transition temperature (° C.) of nematicphase-isotropic phase, A E: dielectric anisotropy value, An: opticalanisotropy value, η: viscosity (mPa·s), Vth: threshold voltage (V), P:pitch (μm) of twist, and VHR: voltage holding ratio (%).

In this connection, η was determined at 20° C.; Δε, Δn, Vth, and P weredetermined at 25° C., respectively; and VHR indicates the valuedetermined at 25° C., 80° C., or 100° C. from the left hand side inturn.

EXAMPLE 2

(Use Example 1)

Liquid crystal composition (A) comprising the followingcyanophenylcyclohexane type liquid crystalline compounds in the amountshown below

4-(trans-4-propylcylohexyl) benzonitrile 24% 4-(trans-4-pentylcylohexyl)benzonitrile 36% 4-(trans-4-heptylcylohexyl) benzonitrile 25%4-(trans-4-pentylcylohexyl)-4′-cyanobiphenyl 15%

had the following physical properties:

NI: 71.7, Δε 10.0, Δn 0.137, η: 26.7, Vth:1.78

Liquid crystal composition (B) comprising 85% of the composition (A) and15% of the2″,2′,6′,3,4-pentafluoro-4″-(2-(4-propylphenyl)ethyl)terphenyl (CompoundNo. 1) obtained in Example 1 had the following physical properties:

NI: 75.2, Δε 11.3, Δn 0.149, η:35.6, Vth:1.71

While this liquid crystal composition (B) was allowed to stand in afreezer at −20° C., development of smectic phase or separation ofcrystals was not observed.

According to a method similar to that of Example 1, the followingcompounds (Compound Nos. 2 through 174) can be synthesized: (In thefollowing, Compound No. is abbreviated to Cpd. No.)

Cpd. No. 2: 1-B(3,5F)B(3F)BB-F

Cpd. No. 3: 2-B(3,5F)BB(3F)B-CF₃

Cpd. No. 4: 3-B(3,5F)BBB(3F)-CF₂H

Cpd. No. 5: 4-B(3F)B(3,5F)BB-CFH₂

Cpd. No. 6: 5-BB(3,5F)B(3F)B-OCF₃

Cpd. No. 7: 6-BB(3,5F)BB(3F)-OCF₂H

Cpd. No. 8: 7-B(3F)BB(3,5F)B-OCF₂CF₂H

Cpd. No. 9: 8-BB(3F)B(3,5F)B-OCF₂CFHCF₃

Cpd. No. 10: 2-BBB(3; 5F)B(3F)-OCF₃ NI: 74.1, Δε 11.3, Δn 0.139, κ: 27.6

Cpd. No. 11: 3O-BBB(3,5F)B(3F)-OCF₂CH₂CF₃

Cpd. No. 12: 3O-B(3F)BBB(3,5F)-F

Cpd. No. 13: 1O5-BB(3F)BB(3,5F)-CL

Cpd. No. 14: 18-BBB(3F)B(3,5F)-CF₃

Cpd. No. 15: 13O-B(3F)B(3F)B(3F)B-CF₂H

Cpd. No. 16: 1O3O-B(3F)BB(3F)B(3F)-CFH₂

Cpd. No. 17: 1-BB(3F)B(3F)B(3F)-OCF₃

Cpd. No. 18: 2-B(3F)B(3F)BB(3F)-OCF₂H

Cpd. No. 19: 3-B(3,5F)B(3,5F)BB-CF₂CF₂H

Cpd. No. 20: 4-B(3,5F)BB(3,5F)B-CF₂CFHCF₃

Cpd. No. 21: 5-B(3,5F)BBB(3,5F)-CF₂CH₂CF₃

Cpd. No. 22: 6-B 3,5F)B(3F)B(3F)B-CL

Cpd. No. 23: 7-B(3,5F)B(3F)BB(3F)-F

Cpd. No. 24: 8-B(3,5F)BB(3F)B(3F)-CF₃

Cpd. No. 25: 9-BB(3,5F)B(3,5F)B-CF₂H

Cpd. No. 26: 1 9-BB(3,5F)BB(3,5F)B-CF₂H

Cpd. No. 27: 3-B(3F)B(3,5F)B(3F)B-OCF₃

Cpd. No. 28 3-B(3F)B(3,5F)B(3F)B-OCF₂H

Cpd. No. 29: 3-BB(3,5F)B(3F)B(3F)-C ₂F₅

Cpd. No. 30: 2-BBB(3,5F)B(3,5F)-F

Cpd. No. 31: 2-B(3F)B(3F)B(3,5F)B-CL

Cpd. No. 32: 5-B(3F)BB(3,5F)B(3F)-CF₃

Cpd. No. 33: 5-BB(3F)B(3,5F)B(3-F)-CF₂H

Cpd. No. 34 5-B(3F)B(3F)BB(3,5F)-CFH₂

Cpd. No. 35: 4-B(3F)BB(3F)B(3,5F)-OCF₃

Cpd. No. 36: 4-BB(3F)B(3F)B(3,5F)-OCF₂H

Cpd. No. 37: 4-B(3F)B(3F)B(3F)B(3F)-OCF₂ CF₂H

Cpd. No. 38: 3-B(3,5F)B(3,5F)B(3F)B-F

Cpd. No. 39: 3-B(3,5F)B(3,5F)BB(3F)-CL

Cpd. No. 40: 3-B(3,5F)B(3F)B(3,5F)B-CF₃

Cpd. No. 41: 3-B(3,5F)BB(3,5F)B(3F)-CF₂H

Cpd. No. 42: 3-B(3,5F)B(3F)BB(3,5F)-CFH₂

Cpd. No. 43: 4-B(3,5F)BB(3F)B(3,5F)-OCF₃

Cpd. No. 44: 4-B(3,5F)B(3F)B(3F)B(3F)-OC F₂H

Cpd. No. 45: 4-B(3F)B(3,5F)B(3,5F)B-OCF₂ CFHCF₃

Cpd. No. 46: 4-BB(3,5F)B(3,5F)B(3F)-F

Cpd. No. 47: 4-B(3F)B(3,5F)BB(3,5F)-CL

Cpd. No. 48: 5O-BB(3,5F)B(3F)B(3,5F)-CF₃

Cpd. No. 49: 3-B(3F)B(3,5F)B(3F)B(3F)-CL NI: 72.1, Δε 11.2, Δn 0.139, η:26.6

Cpd. No. 50: 2-B(3F)B(3,5F)B(3F)B(3F)-F

Cpd. No. 51: 2-B(3F)BB(3,5F)B(3,5F)-CL

Cpd. No. 52: 2-BB(3F)B(3,5F)B(3,5F)-CF₃

Cpd. No. 53 1-B(3F)B(3F)B(3,5F)B(3F)-CF₂H

Cpd. No. 54: 2-B(3F)B(3F)B(3F)B(3,5F)-CF H₂

Cpd. No. 55: 5-B(3,5F)B(3,5F)B(3F)B(3F)—OCF₃

Cpd. No. 56: 5-B(3,5F)B(3F)B(3,5F)B(3F)—OCF₂H

Cpd. No. 57: 5-B(3,5F)B(3F)B(3F)B(3,5F)—F

Cpd. No. 58 5-BB(3,5F)B(3,5F)B(3,5F)-CL

Cpd. No. 59: 5-B(3F)B(3,5F)B(3,5F)B(3F)—OCF₂CH₂CF₃

Cpd. No. 60: 6-B(3F)B(3F)B(3,5F)B(3,5F)—CF₃

Cpd. No. 61: 6-B(3,5F)B(3,5F)B(3,5F)B(3,5F)-CF₂H

Cpd. No. 62: 3-B(3,5F)BB(3F)B-1

Cpd. No. 63: 3-BBB(3,6F)B(3F)-O5

Cpd. No. 64: 5-BB(3,6F)BB(2F)-10

Cpd. No. 65: 5-BB(3F)B(2,5F)B-3

Cpd. No. 66: 4O-B(2F)BBB(3F)-O2

Cpd. No. 67: 18-BB(3F)B(2,3F)B-12

Cpd. No. 68: 5-B(3F)BB(2,3F)B-2

Cpd. No. 69: 4-BB(3,5F)B(3F)B(3F)-1

Cpd. No. 70: 3-B(3F)B(3,6F)BB(3F)-3

Cpd. No. 71: 3O-B(2,3F)BB(2,3F)B-2

Cpd. No. 72: 5-BB(2,3F)B(2,3F)B-5

Cpd. No. 73: 5-BB(3,6F)BB(2,3F)-1

Cpd. No. 74: 7-B(3,5F)BB(3,5F)B(3F)-3

Cpd. No. 75: 3O1-B(2,3F)BB(2F)B(2,3F)-2

Cpd. No.76: 1O5-BB(2,3F)B(2,3F)B(2F)-1

Cpd. No. 77: 1O2O-B(3,5F)B(3F)B(3F)B(3,5F)—2

Cpd. No. 78: 2-BB(2,3F)B(3,6F)B(2,3F)-1

Cpd. No. 79: 3-B(2,5F)B(2,3F)BB(2,3F)-3

Cpd. No. 80: 3-B(2,3F)BB(2,3F)B(2,3F)-4

Cpd. No. 81: 5-B(2,3F)B(2,3F)B(2,3F)B(2,3F)-3

Cpd. No. 82: 1-B(3,5F)2B(3F)BB-F

Cpd. No. 83: 2-B(3F)2B(3,5F)BB-CL

Cpd. No. 84: 3-B(3F)2BB(3,5F)B-CF₃

Cpd. No. 85: 4-B(3F)2BBB(3,5F)-OCF₃

Cpd. No. 86: 5-B(3F)2B(3F)B(3F)B-OCF₂H

Cpd. No. 87: 6-B(3F)2BB(3F)B(3F)-CF₂H

Cpd. No. 88: 7-B(3,5F)2BB(3,5F)B-OCF₂CF₂H

Cpd. No. 89: 8-B(3,5F)2B(3F)BB(3F)-OCF₂C FHCF₃

Cpd. No. 90: 5O-B2B(3,5F)BB(3,5F)-F

Cpd. No. 91: 2O2-B2B(3,5F)B(3F)B(3F)-CL

Cpd. No. 92: 3-B(3F)2BB(3,5F)B(3F)-CF₃

Cpd. No. 93: 3-B(3F)2BB(3F)B(3,5F)-OCF₂H

Cpd. No. 94: 4-B(3,5F)2B(3,5F)BB(3F)-OCF₃

Cpd. No. 95: 4-B(3,5F)2BB(3,5F)B(3F)-CF₂H

Cpd. No. 96: 5-B(3F)2B(3,5F)B(3F)B(3F)-CF₂H

Cpd. No. 97: 5-B(3F)2BB(3,5F)B(3,5F)-CL

Cpd. No. 98: 6-B(3F)2B(3F)B(3F)B(3,5F)-CFH₂

Cpd. No. 99: 2O1O-B(3F)2B(3,5F)B(3,5F)B (3F)-CF₃

Cpd. No. 100: 1-B2B(3F)B(3,5F)B-2

Cpd. No. 101: 2-B(2,3F)2B(3F)BB-3

Cpd. No. 102: 3-B2B(3F)B(2,3F)B-4

Cpd. No. 103: 5-B(3F)2B(3,5F)B(3,5F)B-1

Cpd. No. 104: 5-B2B(3,6F)B(2F)B(2,3F)-O2

Cpd. No. 105: 4O-B(2,3F)2B(3,6F)BB(2,3F)—O1

CpC. No. 106: 7-B(3,5F)B2B(3F)B-F

Cpd. No. 107: 6-BB(3,5F)2B(3F)B-CL

Cpd. No. 108: 5-BB(3F)2B(3,5F)B-CF₃

Cpd. No. 109: 4-BB(5F)2BB(3,5F)-OCF₃

Cpd. No. 110: 3-B(3F)B(3F)2BB(3F)-CF₂H

Cpd. No. 111: 2-B(3,5F)B(3,5F)2BB-OCF₂CH₂ CF₂

Cpd. No. 112: 1O-B(3,5F)B2BB(3,5F)-F

CPd. No. 113: 2O1-B(3,5F)B2B(3F)B(3F)-CL

Cpd. No. 114: 5-B(3F)B(3,5F)2B(3F)B-OCF₃

Cpd. No. 115: 4-BB(3F)2B(3,5F)B(3F)-CF₂H

Cpd. No. 116: 2-BB(3F)2B(3F)B(3,5F)-CFH₂

Cpd. No. 117: 3-B(3,5F)B(3F)2B(3F)B(3F)—F

Cpd. No. 118: 3-B(3F)B(3,5F)2B(3,5F)B-F

Cpd. No. 119: 6-B(3F)B(3,5F)2BB(3,5F)-CL

Cpd. No. 120: 5-BB(3F)2B(3,5F)B(3,5F)-OC F₂H

Cpd. No. 121: 4-B(3F)B(3,5F)2B(3,5F)B(3 F)-CF₃

Cpd. No. 122: 2-B(3,5F)B(3,5F)2B(3,5F)B (3,5F)-CFH₂

Cpd. No. 123: 4O-BB2B(3,6F)B(2F)-O2

Cpd. No. 124: 3-BB(3,5F)2B(3F)B(3F)-O4

Cpd. No. 125: 4-BB(2,3F)2B(2F)B(2F)-3

Cpd. No. 126: 5-BB(3,6F)2B(3,6F)B(2F)-2

Cpd. No. 127: 5-BB(3,5F)2B(3,5F)B(3F)-3

Cpd. No. 128: 4-B(2F)B(2,3F)2B(2,3F)B(3 F)-2

Cpd. No. 129: 1-B(3,5F)BB2B(3F)-F

Cpd. No. 130: 3-BB(3,5F)B2B(3F)-CL

Cpd. No. 131: 5-BBB(3,5F)2B(3F)-CF₃

Cpd. No. 132: 7-BBB(3F)2B(3,5F)-OCF₃

Cpd. No. 133: 9-BB(3F)B(3F)2B(3F)-OCF₂H

Cpd. No. 134: 6O-B(3,5F)BB(3,5F)2B-F

Cpd. No. 135: 5O1-B(3,5F)B(3F)B(3F)2B-OC F₂CF₂H

Cpd. No. 136: 1O4-BB(3,5F)B(3,5F)2B-OCF₂CFHCF₃

Cpd. No. 137: 1O2O-B(3F)B(3,5F)B2B(3F)-OCF₂H

Cpd. No. 138: 15O-B(3F)B(3F)B(3,5F)2B-OCF₃

Cpd. No. 139: 3-B(3F)B(3F)B2B(3,5F)-CF₃

Cpd. No. 140: 3-B(3,5F)B(3,5F)B(3F)2B-F

Cpd. No. 141: 5-B(3,5F)B(3F)B(3,5F)2B-CL

Cpd. No. 142: 4-BB(3,5F)B(3,5F)2B(3F)-CF₃

Cpd. No. 143: 2-BB(3,5F)B(3F)2B(3,5F)-OC F₃

Cpd. No. 144: 6-B(3F)B(3F)B(3,5F)2B(3F)—CF₂H

Cpd. No. 145: 3-B(3F)B(3,5F)B(3F)2B(3,5 =F)-CF₂H

Cpd. No. 146: 3-BBB(3F)2B(2,3F)-O1

Cpd. No. 147: 4O-B(2,3F)BB(2,3F)2B-3

Cpd. No. 148: 5-BB(2,3F)B(3,6F)2B-1

Cpd. No. 149: 30-B(2,3F)B(2,3F)B2B(3F)-O4

Cpd. No. 150: 6-B(2,3F)BB(2,3F)2B(2,3F)—3

Cpd. No. 151: 3-BB(2,3F)B(2,3F)2B(2,5F)—O7

Cpd. No. 152: 3-B4B(3F)B(3,5F)B-F

Cpd. No. 153: 4-B4B(3,5F)B(3F)B(3F)-CL

Cpd. No. 154: 5-B(3,5F)4-B(3,5F)B(3F)B-OC F₃

Cpd. No. 155: 3O-B(3F)4B(3,5F)B(3F)B(3F)—OCF₃

Cpd. No. 156: 5-B(2F)4BBB(2,3F)-O1

Cpd. No. 157: 5-B(2,3F)4BBB(2,3F)-3

Cpd. No. 158: 6-B(2,3F)4B(3F)BB(2,3F)-F

Cpd. No. 159: 3O-B(2,5F)4B(2,3F)BB(3,6F)—3

Cpd. No. 160: 5-BB(3,5F)4BB(3F)-CL

Cpd. No. 161: 3-B(3F)B(3F)4B(3F)B(3F)-OC F₂H

Cpd. No. 162: 2-BB(3F)4B(3,5F)B(3,5F)-C F₂H

Cpd. No. 163: 4-B(3F)B(3,5F)4B(3,5F)B-CF H₂

Cpd. No. 164: 3-BB4B(3,6F)B(2F)-2

Cpd. No. 165: 5-BB(3,6F)4B(2,5F)B-5

Cpd. No. 166: 2-BB(2,5F)4B(3,6F)B(3F)-1

Cpd. No. 167: 5-B(2,3F)B4B(2,3F)B(2,3F)-O2

Cpd. No. 168: 2-B(3,5F)BB(3F)4B-CL

Cpd. No. 169: 3-BBB(3,5F)4B(3,5F)-F

Cpd. No. 170: 6-B(3F)BB(3,5F)4B(3,5F)-OC F₃

Cpd. No. 171: 5O-BB(2,3F)B(3F)4B-3

Cpd. No. 172: 3O-B(2F)BB(2,3F)4B(5F)-3

Cpd. No. 173: 4-BB(2,3F)B(2,3F)4B(3F)-3

Cpd. No. 174: 5-BB(3,6F)B(3,6F)4B(3,6F)—2

EXAMPLE 3

Preparation of2″,5″,2′-trifluoro-4-trifluoromethyl-4″-((4-pentyloxyphenyl)methoxy)terphenyl(5O-BCH₂OB(3,5F)B(3F)B—CF₃(Compound No. 175))

To a mixture of 0.7 g (corresponding to 162.9 mmol) of NaH (60%) and 5ml of dimethyl formamide (DMF) was added dropwise a solution of 5.0 g(135.8 mmol) of 2″,5″,2′-trifluoro-4-trifluoromethyl-4″-hydroxyterphenylin 60 ml of DMF at room temperature. After finishing of the dropping,they were stirred for 1 hour. Subsequently, a solution of 6.2 g (203.6mmol) of 1-iodomethyl-4-pentyloxybenzene in 30 ml of DMF was addeddropwise thereto at room temperature. After finishing of the dropping,they were stirred for 3 hours. The mixture thus formed was poured into150 ml of a diluted hydrochloric acid and extracted with 100 ml oftoluene. The organic layer thus obtained was washed with an aqueoussodium bicarbonate solution and water, and then dried over anhydrousmagnesium sulfate. The solvent was distilled off under a reducedpressure, and the residue thus obtained was subjected to silica gelcolumn chromatography (eluent: heptane/toluene=1/1) to obtain a crude2″,5″-2′-trifluoro-4-trifluoromethyl-4″-((4-pentyloxyphenyl)methoxy)terphenyl.This product was recrystallized from mixed solvent of ethanol/ethylacetate (8/2) to obtain the subject compound.

According to a method similar to that of Example 3, the followingcompounds (Compound Nos. 176 through 214) can be prepared:

Cpd. No. 176:2-BB(3F)CH₂OBB(3,5F)-CL

Cpd. No. 177: 2-BB(3F)B(3F)CH₂OB(3F)-CF₃

Cpd. No. 178: 5-BCH₂OB(3F)B(3,5F)B(3F)-F

Cpd. No. 179: 3-BB(3,5F)CH₂OBB(3,5F)-CF₃

Cpd. No. 180: 2-B(3F)B(3F)B(3F)CH₂OB(3F)—OCF₃

Cpd. No. 181: 3-B(3,5F)CH₂OB(3F)B(3,5F)B—OCF₃

Cpd. No. 182: 4-B(3F)B(3F)CH₂OB(3F)B(3,5 F)-OCF₂CFHCF₃

Cpd. No. 183: 3-BB(3,5F)B(3,5F)CH₂OB(3F)—OCF₂H

Cpd. No. 184: 4-BCH₂OB(3,5F)B(3,5F)B(3,5 F)-OCF₂H

Cpd. No. 185: 5-B(3F)B(3,5F)CH₂OB(3F)B(3,5F)-CF₂H

Cpd. No. 186: 15-B(3,5F)B(3F)B(3,5F)CH₂OB(3F)-F

Cpd. No. 187: 20-BCH₂OB(2F)BB(2,3F)-2

Cpd. No. 188: 3-BCH₂OB(2F)B(3,6F)B(3F)-5

Cpd. No. 189: 5-B(2F)CH₂OB(2F)B(3,6F)B(2 F)-4

Cpd. No. 190: 6-B(2,3F)CH₂OB(2F)B(2F)B(2,3 F)-1

Cpd. No. 191: 7-BB(3F)B(3F)CH₂OB(2F)-2

Cpd. No. 192: 4O-B(2,3F)BBCH₂OB(2,3F)-O1

Cpd. No. 193: 4-B(2F)B(3F)B(3F)CH₂OB(2,3 F)-O2

Cpd. No. 194: 2-BOCH₂B(3,5F)B(3F)B-CF₃

Cpd. No. 195: 3-BB(3,5F)OCH₂B(3F)B(3F)-F

Cpd. No. 196: 4-BB(3,5F)B(3F)OCH₂B(3,5F)—OCF₃

Cpd. No. 197: 2-BC₃H₆OB(3F)B(3,5F)B-CL

Cpd. No. 198: 3-B(3F)C₃H₆OB(3,5F)B(3F)B-OCF₂H

Cpd. No. 199: 3-B(3F)C₃H₆OB(3,5F)B(3F)B(3F)-CF₃

Cpd. No. 200: 3-B(3F)C₃H₆OB(3,5F)B(3F)B(3,5F)-F

Cpd. No. 201: 5-BC₃H₆OB(2F)B(3,6F)B-3

Cpd. No. 202: 4-BB(3,5F)C₃H₆OBB(3F)-CF₂H

Cpd. No. 203: 6-BB(3F)C₃H₆OB(3,5F)B(3F)-O CF₃

Cpd. No. 204: 7-B(3F)B(3F)C₃H₆OB(3,5F)B(3 F)-F

Cpd. No. 205: 3-B(2,3 F)BC₃H₆OB(2F)B(3F)-1

Cpd. No. 206: 5-B(2,3F)BC₃H₆OB(2,3F)B(2,3F)-O₂

Cpd. No. 207: 5-BB(3F)BC₃H₆OB(3,5F)-CL

Cpd. No. 208: 5-BB (3F)B(3F)C₃H₆OB(3,5F)-OCF₃

Cpd. No. 209: 3-B(3,5F)BB(3F)C₃H₆OB(3,5F)—OCF₂H

Cpd. No. 210: 3-B(2F)B(3,6F)BC₃H₆OB(2,3F)—O1

Cpd. No. 211: 3-BOC₃H₆B(3,5F)BB(3F)-CF₃

Cpd. No. 212: 5-B(3F)B(3F)OC₃H₆B(3F)B(3F)—CF₃

Cpd. No. 213: 5-B-(2,5F)BB(2,3F)OC₃H₆B(3F)

Cpd. No. 214: 3-B(2F)B(2,3,F)OC₃H₆BB(2,3 F)—O4

EXAMPLE 4

(Use Example 2)

Physical properties of the liquid crystal composition of CompositionExample 1 were as follows:

NI: 90.7, Δε: 7.5, Δn: 0.165, μ:15.2, Vth: 2.05, P: 11 μm

While this liquid crystal composition was allowed to stand in a freezerat —20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 5

(Use Example 3)

Physical properties of the liquid crystal composition of CompositionExample 2 were as follows:

NI: 88.6, Δε: 9.1, Δn: 0.153, η: 17.8, Vth: 1.94

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 6

(Use Example 4)

Physical properties of the liquid crystal composition of CompositionExample 3 were as follows:

NI: 90.3, Δε: 31.6, Δn: 0.149, η: 88.5, Vth: 0.85

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 7

(Use Example 5)

Physical properties of the liquid crystal composition of CompositionExample 4 were as follows:

NI: 94.7, Δε: 7.1, Δn: 0.206, η: 35.91 Vth: 2.13

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 8

(Use Example 6)

Physical properties of the liquid crystal composition of compositionExample 5 were as follows:

NI: .66.4, Δε: 11.7, Δn: 0.120, η: 39.3, Vth: 1.28

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 9

(Use Example 7)

Physical properties of the liquid crystal composition of compositionExample 6 were as follows:

NI: 77.5, Δε: 9.1, Δn: 0.142, η: 21.7, Vth: 1.63

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 10

(Use Example 8)

Physical properties of the liquid crystal composition of CompositionExample 7 were as follows:

NI: 75.6, Δε: 24.6, Δn: 0.122, η: 38.4, Vth: 0.97

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 11

(Use Example 9)

Physical properties of the liquid crystal composition of CompositionExample 8 were as follows:

NI: 91.1, Δε: 4.8, Δn: 0.118, η: 16.0, Vth: 2.36

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 12

(Use Example 10)

Physical properties of the liquid crystal composition of CompositionExample 9 were as follows:

NI: 90.3, Δε: 28.7, Δn: 0.142, η: 40.6, Vth: 0.98

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 13

(Use Example 11)

Physical properties of the liquid crystal composition of CompositionExample 10 were as follows:

NI: 61.3, Δε: 10.7, Δn: 0.118, η: 28.2, Vth: 1.30

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 14

(Use Example 12)

Physical properties of the liquid crystal composition of CompositionExample 11 were as follows:

NI: 65.4, Δε: 7.7, Δn: 0.169, η: 25.4, Vth: 1.66

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 15

(Use Example 13)

Physical properties of the liquid crystal composition of CompositionExample 12 were as follows:

NI: 101.3, Δε: 8.3, Δn: 0.135, η: 18.0, Vth: 2.08

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 16

(Use Example 14)

Physical properties of the liquid crystal composition of CompositionExample 13 were as follows:

NI: 99.8, Δε: 7.4, Δn: 0.208, η: 15.6, Vth: 2.01

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 17

(Use Example 15)

Physical properties of the liquid crystal composition of CompositionExample 14 were as follows:

NI: 80.0, Δε: 7.0, Δn: 0.130, η: 13.6, Vth: 2.00

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 18

(Use Example 16)

Physical properties of the liquid crystal composition of CompositionExample 15 were as follows:

NI: 99.7, Δε: 5.7, Δn: 0.106, η: 21.4, Vth: 2.35

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 19

(Use Example 17)

Physical properties of the liquid crystal composition of CompositionExample 16 were as follows:

NI: 80.9, Δε: 11.1, Δn: 0.148, η: 26.5, Vth: 1.70

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 20

(Use Example 18)

Physical properties of the liquid crystal composition of CompositionExample 17 were as follows:

NI: 101.3, Δε: 6.3, Δn: 0.099, η: 27.4, Vth: 2.08, P: 79

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 21

(Use Example 19)

Physical properties of the liquid crystal composition of CompositionExample 18 were as follows:

NI: 88.4, Δε: 3.9, Δn: 0.096, η: 20.2, Vth: 2.52

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 22

(Use Example 20)

Physical properties of the liquid crystal composition of CompositionExample 19 were as follows:

NI: 85.9, Δε: 5.8, Δn: 0.116, η: 25.9, Vth: 1.99

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 23

(Use Example 21)

Physical properties of the liquid crystal composition of CompositionExample 20 were as follows:

NI: 71.9, Δε: 9.1, Δn: 0.089, η: 25.8, Vth: 1.51, VHR: 97.1, 96.4, 95.9

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 24

(Use Example 22)

Physical properties of the liquid crystal composition of CompositionExample 21 were as follows:

NI: 73.7, Δε: 13.7, Δn: 0.090, η: 35.3, Vth: 1.32

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 25

(Use Example 23)

Physical properties of the liquid crystal composition of CompositionExample 22 were as follows:

NI: 90.1, Δε: 6.0, Δn: 0.136, η: 23.7, Vth: 2.11

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 26

(Use Example 24)

Physical properties of the liquid crystal composition of CompositionExample 23 were as follows:

NI: 96.5, Δε: 9.4, Δn: 0.116, η: 34.9, Vth: 1.70

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 27

(Use Example 25)

Physical properties of the liquid crystal composition of CompositionExample 24 were as follows:

NI: 83.8, Δε: 4.8, Δn: 0.093, η: 15.7, Vth: 2.35

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 28

(Use Example 26)

Physical properties of the liquid crystal composition of CompositionExample 25 were as follows:

NI: 70.0, Δε: 8.9, Δn: 0.100, η: 27.3, Vth: 1.69

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 29

(Use Example 27)

Physical properties of the liquid crystal composition of CompositionExample 26 were as follows:

NI: 89.6, Δε: 8.3, Δn: 0.137, η: 35.8, Vth: 1.79

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 30

(Use Example 28)

Physical properties of the liquid crystal composition of CompositionExample 27 were as follows:

NI: 72.6, Δε: 5.0, Δn: 0.093, η: 17.8, Vth: 2.09

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 31

(Use Example 29)

Physical properties of the liquid crystal composition of -CompositionExample 28 were as follows:

NI: 101.5, Δε: 8.7, Δn: 0.122, η: 38.7, Vth: 1.71, VHR: 97.7, 96.6, 96.1

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 32

(Use Example 30)

Physical properties of the liquid crystal composition of CompositionExample 29 were as follows:

NI: 95.7, Δε: 9.9, Δn: 0.136, η: 20.8, Vth: 1.95

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 33

(Use Example 31)

Physical properties of the liquid crystal composition of CompositionExample 30 were as follows:

NI: 82.7, Δε: 12.0, Δn: 0.100, η: 33.4, Vth: 1.65

While this liquid crystal composition was allowed to stand in a freezerat −20° C, development of smectic phase or separation of crystals wasnot observed.

EXAMPLE 34

(Use Example 32)

Physical properties of the liquid crystal composition of compositionExample 31 were as follows:

NI: 84.0, Δε: −3.5, Δn: 0.082

While this liquid crystal composition was allowed to stand in a freezerat −20° C., development of smectic phase or separation of crystals wasnot observed.

Liquid crystalline compounds of the present invention have an extremelyhigh voltage holding ratio, are considerably small in its alterationcaused by the change of temperature, and have a low threshold voltageand a high Δn. Further, liquid crystalline compounds having desiredphysical properties can be provided by selecting a proper substituentand bonding group in the liquid crystalline compounds of the presentinvention.

Industrial Applicability

Accordingly, novel liquid crystal compositions having an extremely highvoltage holding ratio, being considerably small in its alteration by thechange of temperature, having a suitable height of Δn and Δε, and beingexcellent in stability and miscibility with other liquid crystalmaterials can be provided by using the liquid crystalline compound ofthe present invention as component of liquid crystal compositions.Further, excellent liquid crystal display devices of in-plane-switching(IPS) mode or vertical alignment (VA) mode can be provided by using theliquid crystal composition.

What is claimed is:
 1. A liquid crystalline compound expressed by thegeneral formula (1)

wherein R represents an alkyl group having 1 to 20 carbon atoms in whichalkyl group any not-adjacent methylene group (—CH₂—) may be replaced byoxygen (—O—) atom; Y₁ to Y₁₆ independently represent hydrogen atom orfluorine atom, but at least three of them are fluorine atoms, providedthat in no case three or more hydrogen atoms of one 1,4-phenylene groupare replaced by fluorine atom; X represents a halogen atom or an alkylgroup having 1 to 20 carbon atoms in which alkyl group any not-adjacentmethylene group may be replaced by oxygen atom, and any hydrogen atom inthe alkyl group may be replaced by fluorine atom; and Z₁, Z₂, and Z₃independently represent —(CH₂)₂—, —(CH₂)₄—, —CH₂O—, —OCH₂—, —(CH₂)₃O—,—O(CH₂)₃—, or single bond; provided that when X=—OCF₂CF₂H, Z₁=Z₃=singlebond, and Z₂=—(CH₂)₂—, in no case Y₆=Y₁₀=Y₁₂=F, and Y₁ to Y₅ =Y₇ toY₉=Y₁₁=Y₁₃ to Y₁₆=H, Y₂=Y₁₀=Y₁₂=F, and Y₁=Y₃ to Y₉=Y₁₁=Y₁₃ to Y₁₆=H, orY₂=Y₄=Y₁₀=Y₁₂=F, and Y₁=Y₃=Y₅ to Y₉=Y₁₁=Y₁₃ to Y₁₆=H.
 2. The liquidcrystalline compound according to claim 1 wherein X is a halogen atom,—CF₃—, —CF₂H, —CFH₂, —OCF₃, —OCF₂H, —OCF₂CH₂CF₃, —OCF₂CFHCF₃, an alkylgroup having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbonatoms, or an alkoxyalkyl group having 1 to 20 carbon atoms.
 3. A liquidcrystal composition comprising at least two components, at least one ofwhich is a liquid crystalline compound defined in claim 1 or
 2. 4. Aliquid crystal composition comprising, as a first component, at leastone compound defined in claim 1 or 2, as a second component, at leastone compound selected from the group consisting of the compoundsexpressed by the general formulas (2), (3), and (4)

wherein R₁ represents an alkyl group having 1 to 10 carbon atoms. inwhich alkyl group any not-adjacent methylene group may be replaced byoxygen atom or —CH═CH—, and any hydrogen atom in the alkyl group may bereplaced by fluorine atom; X₁ represents fluorine atom, chlorine atom,—OCF₃, —OCF₂H, —CF₃, —CF₂H, —CFH₂, —OCF₂CF₂H, or —OCF₂CFHCF₃; L, and L₂independently represent hydrogen atom or fluorine atom; Z₄ and Z₅independently represent 1,2-ethylene group, 1,4-butylene group, —COO—,—CF₂O—, —OCF₂—, —CH═CH—, or single bond; ring B representstrans-1,4-cyclohexylene or 1,3-dioxane-2,5-diyl, or 1,4-phenylene inwhich hydrogen atom may be replaced by fluorine atom; ring C representstrans-1,4-cyclohexylene, or 1,4-phenylene in which hydrogen atom may bereplaced by fluorine atom; and any atom which constitutes thesecompounds may be replaced by its isotope, and optionally, as a thirdcomponent, at least one optically active compound.
 5. A liquid crystalcomposition comprising, as a first component, at least one compounddefined in claim 1 or 2, as a second component, at least one compoundselected from the group consisting of the compounds expressed by thegeneral formulas (5) and (6)

wherein R₂ and R₃ independently represent an alkyl group having 1 to 10carbon atoms in which alkyl group any not-adjacent methylene group maybe replaced by oxygen atom or —CH═CH—, and any hydrogen atom in thealkyl group may be replaced by fluorine atom; X₂ represents —CN or—C≡C—CN; ring D represents trans-1,4-cyclohexylene, 1,4-phenylene,1,3-dioxane-2,5-diyl, or pyrimidine-2,5-diyl; ring E representstrans-1,4-cyclohexylene or pyrimidine-2,5-diyl, or 1,4-phenylene inwhich hydrogen atom may be replaced by fluorine atom; ring F representstrans-1,4-cyclohexylene or 1,4-phenylene; Z₆ represents 1,2-ethylenegroup, —COO—, or single bond; L₃, L₄, and L₅ independently representhydrogen atom or fluorine atom; b, c, and d are independently 0 or 1;and any atom which constitutes these compounds may be replaced by itsisotope, and optionally, as a third component, at least one opticallyactive compound.
 6. A liquid crystal composition comprising, as a firstcomponent, at least one compound defined in claim 1 or 2, as a secondcomponent, at least one compound selected from the group consisting ofthe compounds expressed by the general formulas (2), (3), and (4)

wherein R₁ represents an alkyl group having 1 to 10 carbon atoms. inwhich alkyl group any not-adjacent methylene group may be replaced byoxygen atom or —CH═CH—, and any hydrogen atom in the alkyl group may bereplaced by fluorine atom; X₁ represents fluorine atom, chlorine atom,—OCF₃, —OCF₂H, —CF₃, —CF₂H, —CFH₂, —OCF₂CF₂H, or —OCF₂CFHCF₃; L₁ and L₂independently represent hydrogen atom or fluorine atom; Z₄ and Z₅independently represent 1,2-ethylene group, 1,4-butylene group, —COO—,—CF₂O—, —OCF₂—, —CH═CH—, or single bond; ring B representstrans-1,4-cyclohexylene or 1,3-dioxane-2,5-diyl, or 1,4-phenylene inwhich hydrogen atom may be replaced by fluorine atom; ring C representstrans-1,4-cyclohexylene, or 1,4-phenylene in which hydrogen atom may bereplaced by fluorine atom; and any atom which constitutes thesecompounds may be replaced by its isotope, as a third component, at leastone compound selected from the group consisting of the compoundsexpressed by the general formulas (7), (8), and (9)

wherein R₄ and R₅ independently represent an alkyl group having 1 to 10carbon atoms in which alkyl group any not-adjacent methylene group maybe replaced by oxygen atom or —CH═CH—, and any hydrogen atom in thealkyl group may be replaced by fluorine atom; ring G, ring I, and ring Jindependently represent trans-1,4-cyclohexylene or pyrimidine-2,5-diyl,or 1,4-phenylene in which hydrogen atom may be replaced by fluorineatom; Z₇ and Z₈ independently represent —C≡C—, —COO—, —CH₂CH₂—, —CH═CH—,or single bond; and any atom which constitutes these compounds may bereplaced by its isotope, and optionally, as a fourth component, at leastone optically active compound.
 7. A liquid crystal compositioncomprising, as a first component, at least one compound defined in claim1 or 2, as a second component, at least one compound selected from thegroup consisting of the compounds expressed by the general formulas (5)and (6),

wherein R₂ and R₃ independently represent an alkyl group having 1 to 10carbon atoms in which alkyl group any not-adjacent methylene group maybe replaced by oxygen atom or —CH═CH—, and any hydrogen atom in thealkyl group may be replaced by fluorine atom; X₂ represents —CN or—C≡C—CN; ring D represents trans-1,4-cyclohexylene, 1,4-phenylene,1,3-dioxane-2,5-diyl, or pyrimidine-2,5-diyl; ring E representstrans-1,4-cyclohexylene or pyrimidine-2,5-diyl, or 1,4-phenylene inwhich hydrogen atom may be replaced by fluorine atom; ring F representstrans-1,4-cyclohexylene or 1,4-phenylene; Z₆ represents 1,2-ethylenegroup, —COO—, or single bond; L₃, L₄, and L₅ independently representhydrogen atom or fluorine atom; b, c, and d are independently 0 or 1;and any atom which constitutes these compounds may be replaced by itsisotope, as a third component, at least one compound selected from thegroup consisting of the compounds expressed by general formulas (7),(8), and (9)

wherein R₄ and R₅ independently represent an alkyl group having 1 to 10carbon atoms in which alkyl group any not-adjacent methylene group maybe replaced by oxygen atom or —CH═CH—, and any hydrogen atom in thealkyl group may be replaced by fluorine atom; ring G, ring I, and ring Jindependently represent trans- 1,4-cyclohexylene or pyrimidine-2,5-diyl,or 1,4-phenylene in which hydrogen atom may be replaced by fluorineatom; Z₇ and Z₈ independently represent —C≡C—, —COO—, —CH₂CH₂—, —CH═CH—,or single bond; and any atom which constitutes these compounds may bereplaced by its isotope, and optionally, as a fourth component, at leastone optically active compound.
 8. A liquid crystal compositioncomprising, as a first component, at least one compound defined in claim1 or 2, as a second component, at least one compound selected from thegroup consisting of the compounds expressed by the general formulas(10), (11), and (12)

wherein R₆ and R₇ independently represent an alkyl group having 1 to 10carbon atoms in which alkyl group any not-adjacent methylene group maybe replaced by oxygen atom or —CH═CH—, and any hydrogen atom in thealkyl group may be replaced by fluorine atom; ring K and ring Mindependently represent trans-1,4-cyclohexylene or 1,4-phenylene; L₆ andL₇ independently represent hydrogen atom or fluorine atom, but in nocase L₆ and L₇ simultaneously represent hydrogen atom; Z₉ and Z₁₀independently represent —CH₂CH₂—, —COO—, or single bond; and any atomwhich constitutes these compounds may be replaced by its isotope, andoptionally, as a third component, at least one optically activecompound.
 9. A liquid crystal composition comprising, as a firstcomponent, at least one compound defined in claim 1 or 2, as a secondcomponent, at least one compound selected from the group consisting ofthe compounds expressed by the general formulas (7), (8), and (9)

wherein R₄ and R₅ independently represent an alkyl group having 1 to 10carbon atoms in which alkyl group any not-adjacent methylene group maybe replaced by oxygen atom or —CH═CH—, and any hydrogen atom in thealkyl group may be replaced by fluorine atom; ring G, ring I, and ring Jindependently represent trans-1,4-cyclohexylene or pyrimidine-2,5-diyl,or 1,4-phenylene in which hydrogen atom may be replaced by fluorineatom; Z₇ and Z₈ independently represent —C≡C—, —COO—, —CH₂CH₂—, —CH═CH—,or single bond; and any atom which constitutes these compounds may bereplaced by its isotope, as a third component, at least one compoundselected from the group consisting of the compounds expressed by thegeneral formulas (10), (11), and (12)

wherein R₆ and R₇ independently represent an alkyl group having 1 to 10carbon atoms in which alkyl group any not-adjacent methylene group maybe-replaced by oxygen atom or —CH═CH—, and any hydrogen atom in thealkyl group may be replaced by fluorine atom; ring K and ring Mindependently represent trans-1,4-cyclohexylene or 1,4-phenylene; L₆ andL₇ independently represent hydrogen atom or fluorine atom, but in nocase L₆ and L₇ simultaneously represent hydrogen atom; Z₉ and Z₁₀independently represent —CH₂CH₂—, —COO—, or single bond; and any atomwhich constitutes these compounds may be replaced by its isotope, andoptionally, as fourth component, at least one optically active compound.10. A liquid crystal composition comprising, as a first component, atleast one compound defined in claim 1 or 2, as a second component, atleast one compound selected from the group consisting of the compoundsexpressed by the general formulas (2), (3), and (4)

wherein R₁ represents an alkyl group having 1 to 10 carbon atoms. inwhich alkyl group any not-adjacent methylene group may be replaced byoxygen atom or —CH═CH—, and any hydrogen atom in the alkyl group may bereplaced by fluorine atom; X₁ represents fluorine atom, chlorine atom,—OCF₃, —OCF₂H, —CF₃, —CF₂H, —CFH₂, —OCF₂CF₂H, or —OCF₂CFHCF₃; L₁ and L₂independently represent hydrogen atom or fluorine atom; Z₄ and Z₅independently represent 1,2-ethylene group, 1,4-butylene group, —COO—,—CF₂O—, —OCF₂—, —CH═CH—, or single bond; ring B representstrans-1,4-cyclohexylene or 1,3-dioxane-2,5-diyl, or 1,4-phenylene inwhich hydrogen atom may be replaced by fluorine atom; ring c representstrans-1,4-cyclohexylene, or 1,4-phenylene in which hydrogen atom may bereplaced by fluorine atom; and any-atom which constitutes thesecompounds may be replaced by its isotope, as a third component, at leastone compound selected from the group consisting of the compoundsexpressed by the general formulas (5) and (6)

wherein R₂ and R₃ independently represent an alkyl group having 1 to 10carbon atoms in which alkyl group any not-adjacent methylene group maybe replaced by oxygen atom or —CH═CH—, and any hydrogen atom in thealkyl group may be replaced by fluorine atom; X₂ represents —CN or—C≡C—CN; ring D represents trans-1,4-cyclohexylene, 1,4-phenylene,1,3-dioxane-2,5-diyl, or pyrimidine-2,5-diyl; ring E representstrans-1,4-cyclohexylene or pyrimidine-2,5-diyl, or 1,4-phenylene inwhich hydrogen atom may be replaced by fluorine atom; ring F representstrans-1,4-cyclohexylene or 1,4-phenylene; Z₆ represents 1,2-ethylenegroup, —COO—, or single bond; L₃, L₄, and L₅ independently representhydrogen atom or fluorine atom; b, c, and d are independently 0 or 1;and any atom which constitutes these compounds may be replaced by itsisotope, as a fourth component, at least one compound selected from thegroup consisting of the compounds expressed by the general formulas (7),(8), and (9)

wherein R₄ and R₅ independently represent an alkyl group having 1 to 10carbon atoms in which alkyl group any not-adjacent methylene group maybe replaced by oxygen atom or —CH═CH—, and any hydrogen atom in thealkyl group may be replaced by fluorine atom; ring G, ring I, and ring Jindependently represent trans-1,4-cyclohexylene or pyrimidine-2,5-diyl,or 1,4-phenylene in which hydrogen atom may be replaced by fluorineatom; Z₇ and Z₈ independently represent —C≡C—, —COO—, —CH₂CH₂—, —CH═CH—,or single bond; and any atom which constitutes these compounds may bereplaced by its isotope, and optionally, as a fifth component, at leastone optically active compound.
 11. A liquid crystal display devicecomprising the liquid crystal composition defined in claim 3.